LIFEDefinition of life—Comparison with a flame—Organism and organization—Machine theory of life—Organisms without organs: monera—Organization and life of the chromacea—Stages of organization—Complex organisms—Symbolic organisms—Organic compounds—Organisms and inorganic bodies compared in regard to matter, form, and function—Crystalloid and colloid substances—Life of crystals—Growth of crystals—Waves of growth—Metabolism—Catalysis—Fermentation—Biogenesis—Vital force—Old and new vitalism—Palavitalism—Antivitalism—Neovitalism.As the object of this work is the critical study of the wonders of life, and a knowledge of the truth concerning them, we must first of all form a clear idea of the meaning of "life" and "wonder," or miracle. For thousands of years men have appreciated the difference between life and death, between living and lifeless bodies; the former are called organisms, and the latter known as inorganic bodies. Biology—in the widest sense—is the name of the science which treats of organisms; we might call the science which deals with the inorganic "abiology," abiotik, or anorgik. The chief difference between the two provinces is that organisms accomplish peculiar, periodically repeated, and apparently spontaneous movements, which we do not find in inorganic matter. Hence life may be conceived as a special process of movement. Recent study has shown that this is always connected with a particular chemicalsubstance,plasm, and consists essentially in a circulation of matter, ormetabolism. At the same time modern science has shown that the sharp distinction formerly drawn between the organic and the inorganic cannot be sustained, but that the two kingdoms are profoundly and inseparably united.Of all the phenomena of inorganic nature with which the life-process may be compared, none is so much like it externally and internally as the flame. This important comparison was made two thousand four hundred years ago by one of the greatest philosophers of the Ionic school, Heraclitus of Ephesus—the same thinker who first broached the idea of evolution in the two words,Panta rei—all things are in a state of flux. Heraclitus shrewdly conceived life as a fire, a real process of combustion, and so compared the organism to a torch.Max Verworn has lately employed this metaphor with great effect in his admirable work on general physiology, and has especially dealt with the comparison of the individual life-form with the familiar butterfly shape of the gas-flame. He says:The comparison of life to a flame is particularly suitable for helping us to realize the relation between form and metabolism. The butterfly-shape of a gas-flame has a very characteristic outline. At the base, immediately above the burner, there is still complete darkness; over this is a blue and faintly luminous zone; and over this again the bright flame expands on either side like the wings of a butterfly. This peculiar form of the flame, with its characteristic features, which are permanent, as long as we do not interfere with the gas or the environment, is solely due to the fact that the grouping of the molecules of the gas and the oxygen at various parts of the flame is constant, though the molecules themselves change every moment. At the base of the flame the molecules of the gas are so thickly pressed that the oxygen necessary for their combustion cannot penetrate; hence the darkness we find here. In the bluish zone a few molecules of oxygen have combined with the molecules of the gas: we have a faint light as the result. But in thebody of the flame the molecules of the gas are so freely combined with the oxygen of the atmosphere that we have a lively combustion. However, the exchange of matter (metabolism) between the outpouring gas and the surrounding air is so regulated that we always find the same molecules in the same quantity at the same spot. Thus we get the permanent flame, with all its characteristics. But if we alter the circulation by lessening the stream of gas, the shape of the flame changes, because now the disposition of the molecules on both sides is different. Thus the study of the gas-jet gives us, even in detail, the features we find in the structure of the cell.The scientific soundness of this metaphor is all the more notable as the phrase, "the flame of life," has long been familiar both in poetry and popular parlance.In the sense in which science usually employs the word "organism," and in which we employ it here, it is equivalent to "living thing" or "living body." The opposite to it, in the broad sense, is the anorganic or inorganic body. Hence the word "organism" belongs to physiology, and connotes essentially the visible life-activity of the body, its metabolism, nutrition, and reproduction.However, in most organisms we find, when we examine their structure closely, that this consists of various parts, and that these parts are put together for the evident purpose of accomplishing the vital functions. We call themorgans, and the manner in which they are combined, apparently on a definite plan, is theirorganization. In this respect, we compare the organism to a machine in which some one has similarly combined a number of (lifeless) parts for a definite purpose, but according to a preconceived and rationally initiated design.The familiar comparison of an organism to a machine has given rise to very serious errors in regard to the former, and has, of late, been made the base of false dualistic principles. The modern "machine-theory oflife" which is raised thereon demands an intelligent design and a deliberate constructing engineer for the origin of the organism, just as we find in the case of the machine. The organism is then very freely compared to a watch or a locomotive. In order to secure the regular working of such a complicated mechanism, it is necessary to arrange for a perfect co-operation of all its parts, and the slightest accident to a single wheel suffices to throw it out of gear. This figure was particularly employed by Louis Agassiz (1858), who saw "an incarnate thought of the Creator" in every species of animal and plant. Of late years it has been much used by Reinke in the support of his theosophic dualism. He described God, or "the world-soul," as the "cosmic intelligence," but ascribes to this mystic immaterial being the same attributes that the catechism and the preacher give to the Creator of heaven and earth. He compares the human intelligence which the watch-maker has put into the elaborate structure of the watch with the "cosmic intelligence" which the Creator has put in the organism, and insists that it is impossible to deduce its purposive organization from its material constituents. In this he entirely overlooks the immense difference between the "raw material" in the two cases. The "organs" of the watch are metallic parts, which fulfil their purpose in virtue only of their physical properties (hardness, elasticity, etc.). The organs of the living organism, on the other hand, perform their functions chiefly in virtue of their chemical composition. Their soft plasma-body is a chemical laboratory, the highly elaborate molecular structure of which is the historical product of countless complicated processes of heredity and adaptation. This invisible and hypothetical molecular structure must not (as is often done) be confused with the real and microscopically discoverable structure of the plasm, which is of great importance in the questionof organization. If one is disposed to assume for this molecular structure a simple chemical substance, a deliberate design, and an "intelligent natural force" for cause, one is bound to do the same for powder, and say that the molecules of charcoal, sulphur, and saltpetre have been purposively combined to produce an explosion. It is well known that powder was not made according to a theory, but accidentally discovered in the course of experiment. The whole of this favorite machine-theory of life, and the far-reaching dualistic conclusions drawn from it, tumble to pieces when we study the simplest organisms known to us, the monera; for these are really organisms without organs—and without organization!I endeavored in myGenerelle Morphologie(1866) to draw the attention of biologists to these simplest and lowest organisms which have no visible organization or composition from different organs. I therefore proposed to give them the general title of monera. The more I have studied these structureless beings—cells without nuclei!—since that time, the more I have felt their importance in solving the greatest questions of biology—the problem of the origin of life, the nature of life, and so on. Unfortunately, these primitive little beings are ignored or neglected by most biologists to-day. O. Hertwig devotes one page of his three-hundred-page book on cells and tissues to them; he doubts the existence of cells without nuclei. Reinke, who has himself shown the existence of unnucleated cells among the bacteria (beggiatoa), does not say a word about their general significance. Bütschli, who shares my monistic conception of life, and has given it considerable support by his own thorough study of plasma-structures and the artificial production of them in oil and soap-suds, believes, like many other writers, that the "composition of even the simplestelementary organism from cell-nucleus and protoplasm" (the primitive organs of the cell) is indispensable. These and other writers suppose that the nucleus has been overlooked in the protoplasm of the monera I have described. This may be true for one section of them; but they say nothing about the other section, in which the nucleus is certainly lacking. To this class belong the remarkablechromacea(phycochromaceaorcyanophycea), and especially the simplest forms of these, thechroococcacea(chroococcus,aphanocapsa,glœocapsa, etc.). These plasmodomous (plasma-forming) monera, which live at the very frontier of the organic and inorganic worlds, are by no means uncommon or particularly difficult to find; on the contrary, they are found everywhere, and are easy to observe. Yet they are generally ignored because they do not square with the prevailing dogma of the cell.I ascribe this special significance to the chromacea among all the monera I have instanced because I take them to be the oldest phyletically, and the most primitive of all living organisms known to us. In particular their very simple forms correspond exactly to all the theoretic claims which monistic biology can make as to the transition from the inorganic to the organic. Of the chroococcacea, the chroococcus, glœocapsa, etc., are found throughout the world; they form thin, usually bluish-green coats or jelly-like deposits on damp rocks, stones, bark of trees, etc. When a small piece of this jelly is examined carefully under a powerful microscope, nothing is seen but thousands of tiny blue-green globules of plasma, distributed irregularly in the common structureless mass. In some species we can detect a thin structureless membrane enclosing the homogeneous particle of plasm; its origin can be explained on purely physical principles by "superficial energy"—like the firmer surface-layer of a drop of rain, or of a globule of oil swimmingin water. Other species secrete homogeneous jelly-like envelopes—a purely chemical process. In some of the chromacea the blue-green coloring matter (phyocyan) is stored in the surface-layer of the particle of plasm, while the inner part is colorless—a sort of "central body." However, the latter is by no means a real, chemically and morphologically distinct, nucleus. Such a thing is completely lacking. The whole life of these simple, motionless globules of plasm is confined to their metabolism (orplasmodomism, chapter x.) and the resulting growth. When the latter passes a certain stage, the homogeneous globule splits into two halves (like a drop of quicksilver when it falls). This simplest form of reproduction is shared by the chromacea (and the cognate bacteria) with the chromatella or chromatophora, the green particles of chlorophyll inside ordinary plant-cells; but these are only parts of a cell. Hence no unprejudiced observer can compare these unnucleated and independent granules of plasm with real (nucleated) cells, but must conceive them rather ascytodes. These anatomic and physiological facts may easily be observed in the chromacea, which are found everywhere. The organism of the simplest chromacea is really nothing more than a structureless globular particle of plasm; we cannot discover in them any composition of different organs (or organella) for definite vital functions. Such a composition or organization would have no meaning in this case, since the sole vital purpose of these plasma-particles is self-maintenance. This is attained in the simplest fashion for the individual by metabolism; for the species it is effected by self-cleavage, the simplest conceivable form of reproduction.Modern histologists have discovered a very intricate and delicate structure in many of the higher unicellular protists and in many of the tissue-cells of the higheranimals and plants (such as the nerve-cells). They wrongly conclude that this is universal. In my opinion, this complication of the structure of the elementary organism is always a secondary phenomenon, the slow and gradual result of countless phylogenetic processes of differentiation, initiated by adaptation and transmitted to posterity by heredity. The earliest ancestors of all these elaborate nucleated cells were at first simple, unnucleated cytodes, such as we find to-day in the ubiquitous monera. We shall see more about them in the ninth and fifteenth chapters.Naturally, this lack of a visible histological structure in the plasma-globule of the monera does not exclude the possession of an invisible molecular structure. On the contrary, we are bound to assume that there is such a structure, as in all albuminoid compounds, and especially all plasmic bodies. But we also find this elaborate chemical structure in many lifeless bodies; some of these, in fact, show a metabolism similar to that of the simplest organisms. We will return subsequently to this subject of catalysis. Briefly, the only difference between the simplest chromacea and inorganic bodies that have catalysis is in the special form of their metabolism, which we call plasmodomism (formation of plasm), or "carbon-assimilation." The mere fact that the chromacea assume a globular form is no sign whatever of a morphological vital process; drops of quicksilver and other inorganic fluids take the same shape when the individual body is formed under certain conditions. When a drop of oil falls into a fluid of the same specific gravity with which it cannot mix (such as a mixture of water and spirits of wine), it immediately assumes a globular shape. Inorganic solids usually take the form of crystals instead. Hence the distinctive feature of the simplest organism, the plasma-particles of the monera, is neither anatomic structure nor acertain shape, but solely the physiological function of plasmodomism—a process of chemical synthesis.The difference between the monera I have described and any higher organism is, I think, greater in every respect than the difference between the organic monera and the inorganic crystals. Nay, even the difference between the unnucleated monera (as cytodes) and the real nucleated cells may fairly be regarded as greater still. Even in the simplest real cell we find the distinction between two different organella, or "cell-organs," the internal nucleus and the outer cell-body. Thecaryoplasmof the nucleus discharges the functions of reproduction and heredity; thecytoplasmof the cell-body accomplishes the metabolism, nutrition, and adaptation. Here we have, therefore, the first, oldest, and most important process of division of labor in the elementary organism. In the unicellular protists the organization rises in proportion to the differentiation of the various parts of the cell; in the tissue-forming histona it rises again in proportion to the distribution of work (or ergonomy) among the various organs. Darwin has given us in his theory of selection a mechanical explanation of the apparent design and purposiveness in this.In order to have a correct monistic conception of organization, it is important to distinguish the individuality of the organism in its various stages of composition. We shall treat this important question, about which there is a good deal of obscurity and contradiction, in a special chapter (vii.). It suffices for the moment to point out that the unicellular beings (protists) are simple organisms both in regard to morphology and physiology. On the other hand, this is only true in the physiological sense of the histona, the tissue-forming animals and plants. From the morphological point of view they are made up of innumerable cells, which formthe various tissues. These histonal individuals are called sprouts in the plant world and persons in the animal world. At a still higher stage of organization we have the trunk or stem (cormus), which is made up of a number of sprouts or persons, like the tree or the coral-stem. In the fixed animal stems the associated individuals have a direct bodily connection, and take their food in common; but in the social aggregations of the higher animals it is the ideal link of common interest that unites the individuals, as in swarms of bees, colonies of ants, herds of mammals, etc. These communities are sometimes called "animal-states." Like human polities, they are organisms of a higher type.However, in order to avoid misunderstanding, we must take the word "organism" in the sense in which most biologists use it—namely, to designate an individual living thing, the material substratum of which is plasm or "living substance"—a nitrogenous carbon-compound in a semi-fluid condition. It leads to a good deal of misunderstanding when separate functions are called organisms, as is done sometimes in speaking of the soul or of speech. It would be just as correct to call seeing or running an organism. It is advisable also in scientific treatises to refrain from calling inorganic compounds as such "organisms," as, for instance, the sea or the whole earth. Such names, having a purely symbolical value, may very well be used in poetry. The rhythmic wave-movement of the ocean may be regarded as its respiration, the surge as its voice, and so on. Many scientists (like Fechner) conceive the whole earth with all its organic and inorganic contents as a gigantic organism, whose countless organs have been arranged in an orderly whole by the world-reason (God). In the same way the physiologist, Preyer, regards the glowing heavenly bodies as "gigantic organisms, whose breath is, perhaps, the glowing vaporof iron, whose blood is liquid metal, and whose food may be meteorites." The danger of this poetic application of the metaphorical sense of organism is very well seen in this instance, as Preyer builds on it a quite untenable hypothesis of the origin of life (see chapter xv.).In the wider sense the word "organic" has long been used in chemistry as an antithesis to inorganic. By organic chemistry is generally understood the chemistry of the compounds of carbon, that element being distinguished from all the others (some seventy-eight in number) by very important properties. It has, in the first place, the property of entering into an immense variety of combinations with other elements, and especially of uniting with oxygen, hydrogen, nitrogen, and sulphur to form the most complicated albuminoids (see theRiddle, chapter xiv.). Carbon is a biogenetic element of the first importance, as I explained in my carbon-theory in 1866. It might even be called "the creator of the organic world." At first these organogenetic compounds do not appear in the organism in organized form—that is to say, they are not yet distributed into organs with definite purposes. Such organization is a result, not the cause, of the life-process.I have already shown in the fourteenth chapter of theRiddle(and at greater length in the fifteenth chapter of myHistory of Creation) that the belief in the essential unity of nature, or the monism of the cosmos, is of the greatest importance for our whole system. I gave a very thorough justification of this cosmic monism in 1866. In the fifth chapter of theGenerelle MorphologieI considered the relation of the organic to the inorganic in every respect, pointing out the differences between them on the one hand, and their points of agreement in matter, form, and force on the other. Nägeli some time afterwards declared similarly for the unity of nature in his ableMechanisch-physiologische Begründungder Abstammungslehre(1884). Wilhelm Ostwald has recently done the same, from the monistic point of view of his system of energy, in hisNaturphilosophie, especially in the sixteenth chapter. Without being acquainted with my earlier work, he has impartially compared the physico-chemical processes in the organic and inorganic worlds, partly adducing the same illustrations from the instructive field of crystallization. He came to the same monistic conclusions that I reached thirty-six years ago. As most biologists continue to ignore them, and as, especially, modern vitalism thrusts these inconvenient facts out of sight, I will give a brief summary once more of the chief points as regards the matter, form, and forces of bodies.Chemical analysis shows that there are no elements present in organisms that are not found in inorganic bodies. The number of elements that cannot be further analyzed is now put at seventy-eight; but of these only the five organogenetic elements already mentioned which combine to form plasm—carbon, oxygen, hydrogen, nitrogen, and sulphur—are found invariably in living things. With these are generally (but not always) associated five other elements—phosphor, potassium, calcium, magnesium, and iron. Other elements may also be found in organisms; but there is not a single biological element that is not also found in the inorganic world. Hence the distinctive features which separate the one from the other can be sought only in some special form of combination of the elements. And it is carbon especially, the chief organic element, that by its peculiar affinity enters into the most diverse and complicated combinations with other elements, and produces the most important of all substances, the albuminoids, at the head of which is the living plasm (cf.chapter vi.).An indispensable condition of the circulation of matter (metabolism) which we call life is the physical process ofosmosis, which is connected with the variations in the quantity of water in the living substance and its power of diffusion. The plasm, which is of a spongy or viscous consistency, can take in dissolved matter from without (endosmosis) and eject matter from within (exosmosis). This absorptive property (or "imbibition-energy") of the plasm is connected with the colloidal character of the albuminoids. As Graham has shown, we may divide all soluble substances into two groups in respect of their diosmosis—crystalloids and colloids. Crystalloids (such as soluble salt and sugar) pass more easily into water through a porous wall than colloids (such as albumen, glue, gum, caramel). Hence we can easily separate by dialysis two bodies of different groups which are mixed in a solution. For this we need a flat bottle with side walls of india-rubber and bottom of parchment. If we let this vessel float in a large one containing plenty of water, and pour a mixture of dissolved gum and sugar into the inner vessel, after a time nearly all the sugar passes through the parchment into the water, and an almost pure solution of gum remains in the bottle. This process of diffusion, or osmosis, plays a most important part in the life of all organisms; but it is by no means peculiar to the living substance, any more than the absorptive or viscous condition is. We may even have one and the same substance—either organic or inorganic—in both conditions, as crystal or as colloid. Albumen, which usually seems to be colloidal, forms hexagonal crystals in many plant-cells (for instance, in the aleuron-granules of the endosperm), and tetrahedric hœmoglobin-crystals in many animal-cells (as in the blood corpuscles of mammals). These albuminoid crystals are distinguished by their capacity for absorbing a considerable quantity of water without losing their shape. On the other hand, mineral silicon, which appears as quartz in an immense variety (more than one hundred and sixty)of crystalline forms, is capable in certain circumstances (as metasilicon) of becoming colloidal and forming jelly-like masses of glue. This fact is the more interesting because silicium behaves in other ways very like carbon, is quadrivalent like it, and forms very similar combinations. Amorphous (or non-crystalline) silicium (a brown powder) stands in relation to the black metallic silicon-crystals just as amorphous carbon does to graphite-crystals. There are other substances that may be either crystalloid or colloid in different circumstances. Hence, however important colloidal structure may be for the plasm and its metabolism, it can by no means be advanced as a distinctive feature of living matter.Nor is it possible to assign an absolute distinction between the organic and the inorganic in respect of morphology any more than of chemistry. The instructive monera once more form a connecting bridge between the two realms. This is true both of the internal structure and the outward form of both classes of bodies—of their individuality (chapter vii.) and their type (chapter viii.). Inorganic crystals correspond morphologically to the simplest (unnucleated) forms of the organic cells. It is true that the great majority of organisms seem to be conspicuously different from inorganic bodies by the mere fact that they are made up of many different parts which they use as organs for definite purposes of life. But in the case of the monera there is no such organization. In the simplest cases (chromacea, bacteria) they are structureless, globular, discoid, or rod-shaped plasmic individuals, which accomplish their peculiar vital function (simple growth and subdivision) solely by means of their chemical constitution, or their invisible molecular structure.The comparison of cells with crystals was made in 1838 by the founders of the cell-theory, Schleiden andSchwann. It has been much criticised by recent cytologists, and does not hold in all respects. Still it is of importance, as the crystal is the most perfect form of inorganic individuality, has a definite internal structure and outward form, and obtains these by a regular growth. The external form of crystals is prismatic, and bounded by straight surfaces which cut each other at certain angles. But the same form is seen in the skeletons of many of the protists, especially the flinty shells of the diatomes and radiolaria; their silicious coverings lend themselves to mathematical determination just as well as the inorganic crystals. Midway between the organic plasma-products and inorganic crystals we have thebio-crystals, which are formed by the united plastic action of the plasm and the mineral matter—for instance, the crystalline flint and chalk skeletons of many of the sponges, corals, etc. Further, by the orderly association of a number of crystals we get compound crystal groups, which may be compared to the communities of protists—for instance, the branching ice-flowers and ice-trees on the frozen window. To this regular external form of the crystal corresponds a definite internal structure which shows itself in their cleavage, their stratified build, their polar axes, etc.If we do not restrict the term "life" to organisms properly so-called, and take it only as a function of plasm, we may speak in a broader sense of the life of crystals. This is seen especially in their growth, the phenomenon which Baer regarded as the chief character of all individual development. When a crystal is formed in a matrix, this is done by attracting homogeneous particles. When two different substances, A and B, are dissolved in a mixed and saturated solution, and a crystal of A is put in the mixture, only A is crystallized out of it, not B; on the other hand, if a crystal of B is put in, A remains in solution and B alone assumes thesolid crystalline form. We may, in a certain sense, call this choiceassimilation. In many crystals we can detect internally an interaction of their parts. When we cut off an angle in a forming crystal, the opposite angle is only imperfectly formed. A more important difference between the growth of crystals and monera is that the former only grow byapposition, or the deposit of fresh solid matter at their surface; while the monera grow, like all cells, byintussusception, or the taking of new matter into their interior. But this difference is easily explained by their difference in consistency, the crystal being solid and the plasm semi-fluid. Moreover, the difference is not absolute; there are intermediary stages between apposition and intussusception. A colloid globule suspended in a salt solution in which it is not dissolved may grow by intussusception.It was once the custom to restrict sensation and movement to animals, but they are now recognized to be present in nearly all living matter. They are, in fact, not altogether lacking in crystals, as the molecules move in crystallization in definite directions, and unite according to fixed laws; they must, therefore, also possess sensation, as we could not otherwise understand the attraction of the homogeneous particles. We find in crystallization, as in every chemical process, certain movements which are unintelligible without sensation—unconscious sensation, of course. In this respect, also, then, the growth of all bodies follows the same laws (cf.chapters xiii. and xv.).The growth of a crystal is restricted like the growth of a moneron or of any cell. If the limit is passed and the conditions remain favorable to growth, we find an instance of that excessive ortransgressivegrowth which we call reproduction in the case of living individuals. But we find just the same kind of extension in the inorganic crystal. Every crystal grows in a supersaturatedmedium only up to a definite size, which is determined by its chemical-molecular constitution. When this limit is reached a number of small crystals appear on the large one. Ostwald, who has made a thorough comparison of the process of growth in crystals and monera, especially notices the striking analogy between a bacterium (a plasmophagous moneron) growing and multiplying in its nutritive fluid and a crystal in its matrix. When the water slowly evaporates from a supersaturated solution of Glauber-salt, not only does a crystal slowly grow in it, but several young crystals appear on it. The analogy with the bacterium multiplying in its nutritive fluid can even be followed as far as its permanent forms or "spores." This quiescent form is assumed by the bacterium if its supply of food is exhausted; if fresh food is added, the multiplication by cleavage begins again. In the same way the crystals of Glauber-salt begin to decay when the solution is evaporated; they lose their crystal water, but not their power of multiplication. Even the amorphous powder of the salt causes again the formation of new watery crystals when put in a supersaturated solution. But the powder loses this property when it is heated, just as the dormant forms (or spores) of the bacteria lose their power of germination.The exhaustive comparison of the growth of crystals and monera (as the simplest forms of unnucleated cells) is important, because it shows the possibility of tracing the vital function of reproduction—which had usually been regarded as a quite special "wonder of life"—to purely physical conditions. The division of the growing individual into several young ones must necessarily take place when the natural limit of growth has been passed, and when the chemical composition of the growing body and the cohesion of its molecules allow no further enlargement by the assumption of new matter. In orderto illustrate the limit of this transgressive growth by a simple physical example, Ostwald imagines a ball placed in a small flat basin, built up high on one side. The ball is in a state of equilibrium in the basin; when it is lightly pushed aside it always returns to its original position. But when the push goes beyond a certain point, and the ball is thrust over the side of the basin, the balance is lost; the ball does not return, but falls to the ground. The crystal behaves just in the same way in a supersaturated solution when it exercises its power of forming new crystals; and it is just the same with the bacterium growing in a nutritive fluid when it passes the limit of its volume of growth, and divides into two individuals.As we can find no morphological and little physiological difference between the living and non-living, we must look upon metabolism as the chief characteristic of organic life. This process causes the conversion of food into plasm; it is determined by the vital force itself, and is the formation of new living matter. It thus effects the nutrition and growth of the living being, and therefore its reproduction, which is merely transgressive growth. As I shall describe this metabolism fully in the tenth chapter, I will do no more here than emphasize the fact that this vital process also has analogies in inorganic chemistry, in the curious process of catalysis, especially that form of it which we call fermentation.The distinguished chemist Berzelius discovered in 1810 the remarkable fact that certain bodies, by their mere presence, apart from their chemical affinity, set other bodies in decomposition or composition without being themselves affected. Thus, for instance, sulphuric acid changes the starch in sugar without undergoing any alteration itself. Finely ground platinum brought in contact with hydrogen-superoxide divides it into hydrogen and oxygen. Berzelius called this processcatalysis; Mitscherlich, who discovered the cause of it to be the peculiar surface-action of many bodies, gave it the name of "contact-action." It was afterwards discovered that catalysis of this kind is very general, and that a special form of it—fermentation—plays an important part in the life of organisms.This special form of contact-action which we call fermentation is always effected by catalytic bodies of the albuminoid class, and, in fact, of the group of non-coagulable proteins which are known as peptones. They have—in however small a quantity—the capacity to throw into decomposition large masses of organic matter (in the form of yeast, putrid matter, etc.) without themselves taking part in the decomposition. When these ferments are free and unorganized they are called enzyma, in opposition to organized ferments (bacteria, yeast-fungi, etc.); though the catalytic action of the latter also consists essentially in the production of enzyma. The recent investigations of Verworn, Hofmeister, Ostwald, etc., have shown that these catalyses play everywhere an important part in the life of the plasm. Many recent chemists and physiologists are of opinion that plasm is acolloid catalysator, and that all the varied activities of life are connected with this fundamental vital chemistry. Thus Franz Hofmeister (1901) says in his excellent work onThe Chemical Organization of the Cell:The belief that the agents of the chemical transformation in the cell are catalysators of a colloid nature is in complete accord with other facts that have been directly ascertained. What else are the chemists' ferments but colloid catalysators? The idea that the ferments are the essential chemical agency in the cell is calculated to meet the difficulty which arises from the smallness of the cell in appreciating its chemical processes. However large we suppose the colloid ferment molecules to be, there is room for millions of them in the smallest cell.In the same way Ostwald attributes the greatest significance to catalysis in connection with the vital processes, and seeks to explain them on his theory of energy by reference to the duration of chemical processes. In the discourse "On Catalysis" that he delivered at Hamburg in 1901 he says:We must recognize the enzyma as catalysators that arise in the organism during the life of the cells, and by their action relieve the living being of the greater part of its duties. Not only are digestion and assimilation controlled by enzyma from first to last, but the fundamental vital action of most organisms, the production of the necessary chemical energy by combustion at the expense of the oxygen in the air, takes place with the explicit co-operation of enzyma, and would be impossible without them. Free oxygen is, as is well known, a very inert body at the temperature of the living body, and the maintenance of life would be impossible without some acceleration of its rate of reaction.In his further observations on catalysis and metabolism he says that they are both equally subject to the physico-chemical laws of energy.Max Verworn has given us a very searching analysis of the molecular process in the catalytic aspect of metabolism in hisBiogen Hypothesis(1903), "a critical and experimental study of the processes in living matter." He simplifies the catalytic theory of the enzyma by tracing all the phenomena of life to the catalytic metabolism of one single chemical compound, the plasm, and regards its active molecules, the biogens, as the ultimate chemical factors of the vital process. While the enzyma hypothesis assumes that there are in each cell a great number of different enzyma which are all co-ordinated, and each of which only performs its little special work, the biogen hypothesis deduces all the vital phenomena from one compound, the biogenetic plasm; and thus the biogen molecules, which increase by division into parts,are the sole factors of biological catalysis. Verworn also points out the analogy between this enzymatic process of metabolism and the inorganic processes of catalysis—for instance, in the manufacture of English sulphuric acid. A small and constant quantity of nitromuriatic acid, with the aid of air and water, converts an unlimited mass of sulphuretted acid into sulphuric acid without being changed itself; the molecule of the nitromuriatic acid breaks up steadily by the giving-off of oxygen, and is then restored by the assumption of oxygen.The manifold and changeful phenomena of life and their sudden extinction at death seem to every thoughtful man to be something so wonderful and so different from all the changes in inorganic nature that from the very beginning of biological philosophy special forces were assumed to explain it. This was particularly due to the remarkable, orderly structure of the organism and the apparent purposiveness of the vital processes. Hence, in earlier days a special organic force (archæus insitus) was assumed, controlling the individual life and pressing the "raw forces" of inorganic matter into its service. In the same way a special formative impulse was supposed to preside over the wonderful processes of development. When physiology began to win its independence, about the middle of the eighteenth century, it explained the peculiar features of organic life by a specific vital force. The idea was generally received, and Louis Dumas endeavored thoroughly to establish it at the beginning of the nineteenth century (cf.chapter iii. of theRiddle).As the theory of a vital force, or vitalism, plays an important part in the study of the wonders of life, has undergone the most curious modifications in the course of the nineteenth century, and has been lately revived with great force, we must give a short account of it in its various forms. The phrase can be interpreted in amonistic sense, if we understand by it the sum of the forms of energy which are especially distinctive of the organism, particularly metabolism and heredity. In this we pass no opinion on their nature, and do not say that they are specifically different from the forces of inorganic nature. We might call this monistic conception "physical vitalism." However, the usual metaphysical vitalism affirms in a thoroughly dualistic sense that the vital force is a teleological and super-mechanical principle, is essentially different from the ordinary forces of nature, and of a transcendental character. The special form in which this theory of a supernatural vital force has been presented for the last twenty years is often called Neovitalism; we might call the older form, by contrast, Palavitalism.The older idea of the vital force as a special energy could very well be accepted in the first third of the nineteenth century, and in the eighteenth, because the physiology of the time was destitute of the most important aids to the founding of a mechanical theory. There was then no such thing as the cell-theory or as physiological chemistry; ontogeny and paleontology were still in their cradles. Lamarck's theory of descent (1809) had been done to death, like his fundamental principle: "Life is only an elaborate physical phenomenon." Hence we can easily understand how physiologists acquiesced in the vitalist hypothesis up to 1833, and supposed the wonders of life to be enigmatic phenomena that escaped physical explanation.But the position of Palavitalism changed in the second third of the nineteenth century. In 1833 appeared Johannes Müller's classicalManual of Human Physiology, in which the great biologist not only made a comparative study of the vital phenomena in man and the animals, but sought to provide a sound basis for it in all its sections by his own observations and experiments. Itis true that Müller retained to the last (1858) the current idea of a vital force, as the supreme regulator of all the vital activities. However, he did not regard it as a metaphysical principle (like Haller, Kant, and their followers), but as a natural force, subject, like all others, to fixed chemical and physical laws, and subordinate to the whole. In his comprehensive study of every single vital function—the organs of sense and the nervous system, metabolism and the action of the heart, speech and reproduction—Müller endeavored above all to establish, by close observation of the facts and careful experiments, the regularity of the phenomena, and to explain their development by a comparison of the higher and lower forms. Hence Johannes Müller is wrongly described—as he has been of late—as a vitalist; he was rather the first physiologist to provide a physical foundation for the current metaphysical vitalism. He really gives an indirect proof of the reverse theory, as E. Dubois-Reymond rightly observed in his brilliant memorial speech. In the same way Schleiden (1843) cut the ground from under vitalism in botany. By his cell-theory (1838) he showed the unity of the multicellular organism to be the resultant of the functions of all the cells which compose it.The physical explanation of the vital processes and the rejection of Palavitalism were general in the last third of the nineteenth century. This was due most of all to the great advance in experimental physiology, which Carl Ludwig and Felix Bernard led as regards the animal body, and Julius Sachs and Wilhelm Preyer for the plant. While these and other physiologists used the remarkable results of modern physics and chemistry in the experimental study of the vital functions, and sought to determine their complicated course in terms of mass and weight and formulate their discoveries as mathematically as possible, they brought agreat number of the wonders of life under the same fixed laws that were recognized in the physics and chemistry of the inorganic world. On the other hand, vitalism met with a powerful opponent in Charles Darwin, who solved, by his theory of selection, one of the most obscure biological problems, the constantly repeated question: How can we give a mechanical explanation of the orderly structures of the living being? How was this ingenious machine of the animal or plant body unconsciously produced by natural means, without supposing that some intelligent artificer or creator had deliberately designed and produced it?The further development of Darwin's theory of selection in the last four decades, and the increasing support which has been given to the theory of descent in the great advance of ontogeny, phylogeny, comparative anatomy, and physiology, did much to establish the monistic conception of life. It took the shape more and more of a definite anti-vitalism. Hence it is strange to find that in the course of the last twenty years the old vitalism that everybody had thought dead has lifted up its head once more, though in a new and modified form.[4]This modern vitalism comprises two essentially different tendencies.The partisans of the modern vital force are divided into two groups, which may be designated the sceptical and the dogmatic. Sceptical Neovitalism was first formulated by Bunge, of Basle (1887), in the introduction to hisManual of Physiological Chemistry. While hegranted the possibility of a full explanation of one part of the vital phenomena by mechanical causes, or the physical and chemical forces of lifeless nature, he rejected it for the other half, especially for psychic activities. He insists that the latter cannot be explained mechanically, and that there is nothing analogous to them in inorganic nature; only a supra-mechanical vital force can produce them, and this is transcendental and beyond the range of scientific inquiry. Much the same was said later by Rindfleisch (1888), more recently by Richard Neumeister in hisStudies of the Nature of Vital Phenomena(1903), and by Oscar Hertwig in the lecture on "The Development of Biology in the Nineteenth Century," which he delivered at Aachen in 1900.This sceptical Neovitalism is far surpassed by the dogmatic system, the chief actual representatives of which are the botanist Johannes Reinke and the metaphysician Hans Driesch. The vitalist writings of the latter, which are devoid of any grasp of historical development, have gained a certain vogue through the extraordinary arrogance of their author and the obscurity of his mystic and contradictory speculations. Reinke, on the other hand, has presented his transcendental dualism in clever and attractive form in two works which deserve notice on account of their consistent dualism. In the first of these,The World as Reality(1899), Reinke gives us "the outline of a scientific theory of the universe." The second work (1901) has the title,Introduction to Theoretical Biology. The two works have the same relation to each other as myRiddle of the Universeand the present supplementary volume. As our philosophic convictions are diametrically opposed in the main issues, and as we both think ourselves consistent in developing them, the comparison of them is not without interest in the great struggle of beliefs. Reinke is anavowed supporter of dualism, theism, and teleology. He reduces all the phenomena of life to a supernatural miracle.Second TableANTITHESIS OF THE MONISTIC AND DUALISTIC THEORIES OF ORGANIC LIFEMonistic Theory of Life(Biophysics)Dualistic Theory of Life(Vitalism)1. The phenomena of life are merely functions of plasm, determined by the physical, chemical, and morphological character of the living matter.1. The phenomena of life are wholly or partly independent of the plasm, and determined by a special immaterial force, the vital force (vis vitalis).2. The energy of the plasm (as the sum-total of the forces which are connected with the living matter) is subject to the general laws of physics and chemistry.2. The energy of the plasm is wholly or partly subject to the immaterial vital force, which controls and directs the physical and chemical forces of the living matter.3. The obvious regularity of the vital processes and the organization they produce are the outcome of natural evolution; their physiological factors (heredity and adaptation) are subject to the law of substance.3. The general regularity in the organization and in the vital processes it accomplishes is the outcome of conscious creation; it can only be explained by intelligent immaterial forces which are not subject to the law of substance.4. All the various functions have thus been mechanically produced, orderly structures having been created by adaptation and transmitted to posterity by heredity.4. All the various functions of organisms have been produced by design, the historical evolution (orphyletic transformation) being directed to a preconceived ideal end.5. Nutrition is a physico-chemical process, the metabolism of which has an analogy in inorganic catalysis.5. Nutrition is an inexplicable miracle of life, and cannot be understood by chemical and physical processes.6. Reproduction is a mechanical consequence of transgressive growth, analogous to the elective multiplication of crystals.6. Reproduction is an inexplicable miracle of life, without any analogy in inorganic nature.7. The movement of organisms is, in every form, not essentially different from the movements of inorganic dynamos.7. The movement of organisms is an inexplicable metaphysical miracle of life, specifically different from all inorganic movements.8. Sensation is a general form of the energy of substance, not specifically different in sensitive organisms and irritable inorganic objects (such as powder, dynamite). There is no such thing as an immaterial soul.8. The sensation of organisms can only be explained by ascribing a soul to them, an immaterial, immortal being that only dwells for a time in the body. After death this spirit lives an independent life.IIIMIRACLESMiracle and natural law—Belief in miracles of savages (fetichism), of semi-civilized (idolatry), of civilized (theism), and of educated people (dualism)—Religious belief in miracles—Apostles' Creed—Article relating to creation—Article relating to redemption—Article relating to immortality—Philosophic belief in miracles—Academic thinkers and Free-thinkers—Dualism of Plato and Kant—Belief in miracles in the nineteenth century, in modern metaphysics, theology, and politics.In ordinary parlance the word "miracle" means a number of different things. We say a phenomenon is miraculous or wonderful[5]when we cannot explain it and trace its causes. But we say a natural object or a work of art is wonderful when it is unusually beautiful and imposing—when it passes the ordinary limits of our experience. In this work I do not take the word in this relative sense, but in the absolute sense in which a phenomenon is said to transcend the limits of natural law and lie beyond the range of rational explanation. In this sense it means the same as "supernatural" or "transcendental." We can know natural phenomena by our reason and bring them within our cognizance. The miraculous can only be accepted on faith.The belief in supernatural miracles is in contradiction to pure reason, which lays the foundations of all science. Kant, who won so great a vogue for the term "pure reason," understood by this originally "reason as independent of experience." The phrase was used in a narrower sense subsequently to express independence of dogma and prejudice, as the base of pure and unprejudiced science. In this sense we oppose pure reason to superstition.I have dealt in the sixteenth chapter of theRiddlewith the important question of the relations of knowledge and faith. But I must return to the subject here, as what I said has given rise to a good deal of misunderstanding and criticism. I by no means claimed, as my opponents allege, to "know everything," or to have solved every problem. In fact, I said repeatedly that there are narrow limits to our knowledge, and always will be. I had also expressly stated that the irresistible impulse to learn in the intelligent man, or reason's constant demand to know causes, presses us to fill up the gaps in our knowledge by faith. But I had at the same time pointed out the contrast between scientific (natural) and religious (supernatural) faith. The one leads us to form hypotheses and theories; the other ends in myths and superstition. Scientific faith fills the gaps in our knowledge of natural law with temporary hypotheses; but mystic religious faith contradicts natural law, and transcends its limits in the form of a belief in miracles.The great triumph of the progress of science in the nineteenth century, its theoretical value in the formation of a rational philosophy of life, and its practical value on the various sides of modern civilization, consist, above all, in the absolute recognition of fixed natural laws. That relation of things to each other, which we call causation, makes it possible for us to understand and explain facts. We feel that our thirst for a knowledgeof the causes of things is contented when science points out the "sufficient reason" of them. In the whole province of inorganic cosmology natural law is now generally recognized to be all-powerful; in astronomy, geology, physics, and chemistry all phenomena are reduced to fixed laws, and in the long-run to the all-embracing law of substance, the great law of the conservation of matter and force (Riddle, chapter xii.).It is otherwise in biology, or the organic section of cosmology. Here we still find miracles set up in opposition to the law of substance, and the transgression of natural laws by supernatural forces. The belief in miracles of this kind, which pure reason calls superstition, is still very wide-spread—much more prevalent than is usually thought. For my part, I hold that superstition and unreason are the worst enemies of the human race, while science and reason are its greatest friends. Hence it is our duty and task to attack the belief in miracles wherever we find it, in the interest of the race. We have to prove that the reign of natural law extends over the whole world of phenomena as far as we can reach it. A general survey of the history of faith on the one hand and of science on the other clearly shows that the advance of the latter has always been accompanied by an increasing knowledge of fixed natural laws and the shrinking of superstition into an ever-lessening area. To-day we convince ourselves of this by an impartial examination of mental culture at the various stages of civilization. For this purpose I take the four chief stages of mental development which Fritz Schultze has given in hisPhysiology of Uncivilized Races, and Alexander Sutherland in his work,On the Origin and Growth of the Moral Instinct: 1, savages; 2, barbarians; 3, civilized races; 4, educated races (cf.chapter i.).The mental life of savages rises little above thatof the higher mammals, especially the apes, with which they are genealogically connected. Their whole interest is restricted to the physiological functions of nutrition and reproduction, or the satisfaction of hunger and thirst in the crudest animal fashion. Without fixed habitation, constantly struggling for existence, they live on the raw produce of nature—fruits, the roots of wild plants, and the animals they fish in the water or catch on land. Their intelligence moves within the narrowest bounds, and one can no more (or no less) speak of their reason than of that of the more intelligent animals. Of art and science there is no question. Their impulse to discover causes is satisfied with the simplest association of phenomena which have a merely external connection, but no intimate relation to each other. Thus arises theirfetichism, that irrational trust in fetiches which Fritz Schultze has traced to four distinct causes: their false estimate of the value of an object, their anthropomorphic conception of nature, the imperfect association of their ideas, and the strength of their emotions, especially hope and fear. Any favorite object, a stone or a bone, may work miracles as a fetich and exercise all kinds of good or evil influence, and is therefore honored, feared, and worshipped. At first the worship was paid to the invisible spirit that dwelt in the particular object; but it was often transferred afterwards to the dead object itself. Among the different savage races the belief in fetiches presents a number of stages, corresponding to the beginnings of reason. The lowest stage is found in the lowest races, such as the Veddahs of Ceylon, the Andaman Islanders, Bushmen, and Akkas (of New Guinea). A somewhat higher stage is met in the middle races (Australian negroes, Tasmanians, Hottentots, and Tierra del Fuegians); and a still higher intellectual development is shown by the next group (most of the Indians of North and South America, the aboriginalinhabitants of India, etc.). Modern comparative ethnography and evolution and prehistoric and anthropological research have shown us that our own ancestors, ten thousand and more years ago, were (like the prehistoric ancestors of all races of men) savages, and that their earliest belief in miracles was a crude fetichism.By barbarians we understand the races that are found between savage and civilized peoples. They show the first beginnings of civilization, and are superior to savages chiefly in the possession of agriculture and the keeping of cattle. They make a provident use of the productive forces of organic nature, artificially produce large quantities of food, and are thus enabled by the abundance of food to turn their minds to other interests. We find that they have the rudiments of art and science. Their religion does not at first rise much above fetichism, but soon reaches the stage of animism, lifeless objects in nature being credited with souls. Worship is no longer paid to favorite dead objects (stones, bones, etc.), but generally to living things, trees and animals, and especially to images of gods which have the form of animals or men, and are believed to possess souls. As demons or spirits, these have a great influence on the fortunes of men. At first this soul is conceived to be purely material; it disappears at the death of the body and lives apart. As the breathing and the beat of the pulse and heart cease when a man dies, the seat of the soul is thought to be the lungs, heart, or some other part of the body. The idea of the immortality of the soul takes on innumerable forms among them, like the belief in the miracles which are worked by the gods, demons, spirits, etc. Evolution again points out a long gradation of forms of faith, if we compare the lower, middle, and higher races.Civilized races are distinguished from barbaric by the formation of states with an extensive division of labor.The social organism is not only larger and more powerful, but is capable of a greater variety of achievements, the functions of the various states and classes of workers being more highly differentiated and mutually complementary (like the cells and tissues in the higher animal body of the metazoa). Nutrition is easier and more luxurious. Art and science are well developed. A great advance is seen in regard to religion, the numerous gods being generally conceived as manlike spirits, and finally subordinated to a chief god. The belief in miracles flourishes greatly in poetry; in philosophy it is more and more restricted. In the end, the working of miracles is limited monotheistically to one god, or to his priests and other men to whom he communicates the power.Modern civilization in the narrower sense, as a contrast to the older civilization, opens, in my opinion, at the beginning of the sixteenth century. At that time took place some of the greatest achievements of human thought among civilized peoples, and these broke the chains of tradition and gave a fresh impetus to progress. Men's own mental outlook was widened by the system of Copernicus and the Reformation freed them from the yoke of the papacy. Shortly before, the discovery of the New World and the circumnavigation of the globe had convinced men of the rotundity of the earth; geography, natural history, medicine, and other sciences gained inspiration and independence; printing and engraving provided an important means of spreading the new knowledge. This fresh impetus was chiefly of service to philosophy, which now more and more rejected the dictation of the Church and superstition; though it was far from casting off the fetters altogether. This was not generally possible until the nineteenth century, when empirical science assumed an enormous importance, and in the ensuing period of speculation the physical conceptionof the world gained more and more on the metaphysical. Pure knowledge, thus grounded on science, entered into sharper conflict than ever with religious faith. If, as in the preceding cases, we distinguish three stages in the development of modern civilization, we recognize the progressive liberation from superstition by scientific knowledge.When we compare the higher forms of religion of civilized nations we find the same emotional cravings and thought-processes constantly recurring, and the belief in miracles developing in much the same way. The three founders of the great monotheistic Mediterranean religion—Moses, Christ, and Mohammed—were equally regarded as wonder-working prophets, having direct intercourse with God in virtue of their special gifts, and transmitting his commands to men in the shape of laws. The extraordinary authority they enjoy, which has given so much prestige to the religions they founded, is grounded for ordinary people on their miraculous powers—the healing of the sick, the raising of the dead, the expulsion of devils, and so on. If we examine the miracles of Christ as they are given in the gospels, they run counter to the laws of nature and rational explanation just in the same way as the similar miracles of Buddha and Brahma in Hindoo mythology, or of Mohammed in the Koran. The same must be said of the belief in the miracle of the bread and wine in the Lord's supper, and the like. The Creed which was probably drawn up by the leaders of the Christian communities of the second century, and received its final and present form in the Church of South Gaul in the fourth and fifth centuries, has been obligatory for Christians for fifteen hundred years, and recognized by both Church and State as compulsory. This Apostles' Creed was also recognized in Luther's catechism to be fundamental, and is taught in all Protestant and RomanCatholic schools (though not in the Greek Catholic) as the foundation of religious instruction. This extraordinary prestige of the Apostles' Creed, and its great influence on the education of the young, no less than its glaring inconsistency with rational knowledge, compel us to devote a few pages to a critical examination of its three articles.The first article of the Creed deals with creation, and runs: "I believe in God, the Father Almighty, Creator of heaven and earth." The modern science of evolution has shown that there never was any such creation, but that the universe is eternal and the law of substance all-ruling. God himself is anthropomorphically conceived as an "Almighty Creator" and the Father of man; heaven (in the sense of the geocentric system) is imagined as a great blue vault spanning the earth. The notion of this "personal God" as an intelligent, immaterial being, creating the material world out of nothing, is wholly irrational and meaningless. That Luther accepted this childish and scientifically worthless idea is clear from his commentary on the first article—"What is that?"The second article of the Creed deals with the dogma of salvation in the following words: "I believe in Jesus Christ, his only son, our Lord, who was conceived of the Holy Ghost, born of the Virgin Mary, suffered under Pontius Pilate, was crucified, dead, and buried, descended into hell, on the third day rose again from the dead, ascended into heaven, sitteth at the right hand of God, the Father Almighty, whence he will come to judge the living and the dead." As these dogmas of the second article contain the chief points of the redemption theory, and are still treasured by millions of educated people, it is necessary to point out their flagrant opposition to pure reason. The chief evil of such creeds is that children, who are yet incapable of reflecting, are forced to learnthem by heart. They then remain unchallenged as revealed truths.The myth of the conception and birth of Jesus Christ is mere fiction, and is at the same stage of superstition as a hundred other myths of other religions. Of the three persons who are mysteriously blended in the triune God, the son Christ is supposed to be begotten by both Father and Holy Ghost, parthenogenetically through the Virgin Mary. I have dealt with the physiology of parthenogenesis in the seventeenth chapter of theRiddle. The curious adventures of Christ after his death, the descent into hell, resurrection, and ascension, are also fantastic myths due to the narrow geocentric ideas of an uneducated people. Troelslund has admirably explained the strong influence they have had in his interesting book,The Idea of Heaven and of the World.[6]The idea of the "last judgment," with Christ sitting on the right hand of the Father, as many famous mediæval pictures represent (notably Michael Angelo's in the Sistine Chapel at the Vatican), is another outcome of a thoroughly childish and anthropomorphic attitude.It is remarkable that this second article of the Creed says nothing about "redemption," which forms its heading [in Germany]. Luther has dealt with it in his commentary. Christ is believed to have suffered a painful death, like many thousand other martyrs, for his conviction of the truth of his faith and teaching—which reminds one of the more than a hundred thousand men who were done to death by the Inquisition and in the religious wars of the Middle Ages; but not one of themillions of ministers who preach on it every Sunday seems to have shown a rational causal connection of this death with the alleged redemption from sin and death. The whole of this story of redemption has sprung from the primitive, obscure, ethical ideas of uneducated races, especially the crude belief in the propitiatory power of human sacrifice. It has no practical moral value except for those who believe in personal immortality—a scientifically untenable dogma. Whoever builds on this empty promise of a better life beyond may soothe himself with this hope, and reconcile himself to the thousand ills and defects of this world. But the man who studies this life as it really is will not find that the belief in redemption has brought any real improvement. Want and misery and sin are as prevalent as ever; indeed, our modern civilization has, in many respects, increased them.The third and last article of the Apostles' Creed runs: "I believe in the Holy Ghost, the holy Catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and life everlasting." In the curious commentary that Luther made on this article in his catechism, he said that "man cannot believe of his own reason in Jesus Christ"—which is very true—but the Holy Ghost must lead him thereto with his grace; but how the third person of the Trinity effects this enlightenment and sanctification he did not explain. What is meant by the "communion of saints" and the "holy Catholic Church" must be gathered in the light of their history—especially the history of Romanism. This most powerful and still influential section of the Christian Church, which especially claims the title of Catholic and "the one ark of salvation," is really a most pitiful caricature of pure primitive Christianity. It has, with consummate skill, succeeded in preaching the beneficent teaching of Christ in theory and doing just the oppositein practice; we need only recall the Inquisition, the dark history of the Middle Ages, and the political hierarchy which still dominates so much of civilization.However, by far the most important clause in the third article is the final expression of belief in "the resurrection of the body and life everlasting." That this greatest "wonder of life" was originally conceived in a purely material form is evident from thousands of pictures in which famous painters have realistically depicted the resurrection of the dead, the aërial flight of the happy souls of the blessed, and the torments of the damned in hell. It is thus conceived still by the majority of believers who take eternal life to be an "enlarged and improved edition" of life here below. This is equally true of Christian and Mohammedan pictures and of the athanatist ideas that prevailed in other religions long before Christ was born, even of the first rudiments of the belief in primitive races. As long as the geocentric theory prevailed, and the heavens were thought to be a sort of blue glass bell, illumined by thousands of little stars and the lamp of the sun, arching like a vault over the flat earth, and the fires of hell burned in the cellars below, this barbaric notion of a resurrection of the body and a last judgment could easily be maintained. But its roots were destroyed when Copernicus refuted the geocentric theory in 1545; and athanatism became quite untenable when Darwin shattered the dogma of anthropocentricism. Not only the crude older materialistic idea of eternal life, but also the refined new spiritualistic version, has been rendered untenable by the progress of science in the nineteenth century. I have shown this in the eleventh chapter of theRiddle, which closes with the words: "If we take a comprehensive glance at all that modern anthropology, psychology, and cosmology teach with regard to athanatism, we are forced to this definite conclusion. The belief in the immortality of the humansoul is in hopeless contradiction with the most solid empirical truths of modern science."[7]The great influence which has been exercised on civilized nations by the Christian beliefs, supported by the practical exigencies of the state, for thousands of years, was chiefly seen in the crude superstition of the mass of the people. Confessions of faith became as much a matter of routine as the latest fashion in dress or the latest custom, etc. But even the majority of the philosophers were more or less subordinated to the influence. It is true that a few great thinkers freed themselves by the use of pure reason at an early date from the prevalent superstition, and framed systems apart from tradition and the priests. But most philosophers could not rise to the altitude of these brave Free-thinkers; they remained "school-men" in the literal sense, dependent on the dictation of authority, the traditions of the school, and the dogmas of the Church. Philosophy was the "handmaid" of theology and ecclesiasticism. If we examine the history of philosophy in this light, we find in it a struggle for twenty-five hundred years between two great tendencies—the dualism of the majority (with theological and mystic leanings) and the monism of the minority (with rationalistic and naturalistic disposition).Especially notable are those great Free-thinkers of classic antiquity who taught a monistic view of life in the sixth century before Christ—the Ionic natural philosophers, Thales, Anaximander, and Anaximenes; and a little later, Heraclitus, Empedocles, and Democritus. They made the first thorough attempt to explain the world on rational principles, independently of all mythological tradition and theological dogmas. However,these remarkable efforts to found a primitive monism, which found so finished an expression in theDe rerum naturaof the great poet-philosopher, Lucretius Carus (98-54B.C.), were shortly thrust out by the spread—through Plato's curious dualism—of the belief in the immortality of the soul and the transcendental world of ideas.The Eleatics, Parmenides and Zeno, had foreshadowed in the fifth century the division of philosophy into two branches; but Plato and his pupil Aristotle (in the fourth centuryB.C.) succeeded in gaining general acceptance for this dualism and antithesis of physics and metaphysics. Physics devoted itself on the ground of experience to the study of the phenomena of things, leaving their real essences (or noumena) that lay behind the phenomena to metaphysics. These inner essences are transcendental and inaccessible to empirical research; they form the metaphysical world of eternal ideas, which is independent of the real world, and has its highest unity in God, as the Absolute. The soul, an eternal idea that dwells for a time in the passing human body, is immortal. This consistent dualism of Plato's system, with its sharp antithesis of this world and the next, of body and soul, of world and God, is its chief characteristic. It became all the more influential when Plato's pupil Aristotle blended it with his empirical metaphysics, based on ample scientific experience, and pointed out the idea in the entelechy, or purposively acting principle, of every being; and especially when Christianity (three hundred years afterwards) found in this dualism a welcome philosophic support of its own transcendental tendency.
Definition of life—Comparison with a flame—Organism and organization—Machine theory of life—Organisms without organs: monera—Organization and life of the chromacea—Stages of organization—Complex organisms—Symbolic organisms—Organic compounds—Organisms and inorganic bodies compared in regard to matter, form, and function—Crystalloid and colloid substances—Life of crystals—Growth of crystals—Waves of growth—Metabolism—Catalysis—Fermentation—Biogenesis—Vital force—Old and new vitalism—Palavitalism—Antivitalism—Neovitalism.
As the object of this work is the critical study of the wonders of life, and a knowledge of the truth concerning them, we must first of all form a clear idea of the meaning of "life" and "wonder," or miracle. For thousands of years men have appreciated the difference between life and death, between living and lifeless bodies; the former are called organisms, and the latter known as inorganic bodies. Biology—in the widest sense—is the name of the science which treats of organisms; we might call the science which deals with the inorganic "abiology," abiotik, or anorgik. The chief difference between the two provinces is that organisms accomplish peculiar, periodically repeated, and apparently spontaneous movements, which we do not find in inorganic matter. Hence life may be conceived as a special process of movement. Recent study has shown that this is always connected with a particular chemicalsubstance,plasm, and consists essentially in a circulation of matter, ormetabolism. At the same time modern science has shown that the sharp distinction formerly drawn between the organic and the inorganic cannot be sustained, but that the two kingdoms are profoundly and inseparably united.
Of all the phenomena of inorganic nature with which the life-process may be compared, none is so much like it externally and internally as the flame. This important comparison was made two thousand four hundred years ago by one of the greatest philosophers of the Ionic school, Heraclitus of Ephesus—the same thinker who first broached the idea of evolution in the two words,Panta rei—all things are in a state of flux. Heraclitus shrewdly conceived life as a fire, a real process of combustion, and so compared the organism to a torch.
Max Verworn has lately employed this metaphor with great effect in his admirable work on general physiology, and has especially dealt with the comparison of the individual life-form with the familiar butterfly shape of the gas-flame. He says:
The comparison of life to a flame is particularly suitable for helping us to realize the relation between form and metabolism. The butterfly-shape of a gas-flame has a very characteristic outline. At the base, immediately above the burner, there is still complete darkness; over this is a blue and faintly luminous zone; and over this again the bright flame expands on either side like the wings of a butterfly. This peculiar form of the flame, with its characteristic features, which are permanent, as long as we do not interfere with the gas or the environment, is solely due to the fact that the grouping of the molecules of the gas and the oxygen at various parts of the flame is constant, though the molecules themselves change every moment. At the base of the flame the molecules of the gas are so thickly pressed that the oxygen necessary for their combustion cannot penetrate; hence the darkness we find here. In the bluish zone a few molecules of oxygen have combined with the molecules of the gas: we have a faint light as the result. But in thebody of the flame the molecules of the gas are so freely combined with the oxygen of the atmosphere that we have a lively combustion. However, the exchange of matter (metabolism) between the outpouring gas and the surrounding air is so regulated that we always find the same molecules in the same quantity at the same spot. Thus we get the permanent flame, with all its characteristics. But if we alter the circulation by lessening the stream of gas, the shape of the flame changes, because now the disposition of the molecules on both sides is different. Thus the study of the gas-jet gives us, even in detail, the features we find in the structure of the cell.
The scientific soundness of this metaphor is all the more notable as the phrase, "the flame of life," has long been familiar both in poetry and popular parlance.
In the sense in which science usually employs the word "organism," and in which we employ it here, it is equivalent to "living thing" or "living body." The opposite to it, in the broad sense, is the anorganic or inorganic body. Hence the word "organism" belongs to physiology, and connotes essentially the visible life-activity of the body, its metabolism, nutrition, and reproduction.
However, in most organisms we find, when we examine their structure closely, that this consists of various parts, and that these parts are put together for the evident purpose of accomplishing the vital functions. We call themorgans, and the manner in which they are combined, apparently on a definite plan, is theirorganization. In this respect, we compare the organism to a machine in which some one has similarly combined a number of (lifeless) parts for a definite purpose, but according to a preconceived and rationally initiated design.
The familiar comparison of an organism to a machine has given rise to very serious errors in regard to the former, and has, of late, been made the base of false dualistic principles. The modern "machine-theory oflife" which is raised thereon demands an intelligent design and a deliberate constructing engineer for the origin of the organism, just as we find in the case of the machine. The organism is then very freely compared to a watch or a locomotive. In order to secure the regular working of such a complicated mechanism, it is necessary to arrange for a perfect co-operation of all its parts, and the slightest accident to a single wheel suffices to throw it out of gear. This figure was particularly employed by Louis Agassiz (1858), who saw "an incarnate thought of the Creator" in every species of animal and plant. Of late years it has been much used by Reinke in the support of his theosophic dualism. He described God, or "the world-soul," as the "cosmic intelligence," but ascribes to this mystic immaterial being the same attributes that the catechism and the preacher give to the Creator of heaven and earth. He compares the human intelligence which the watch-maker has put into the elaborate structure of the watch with the "cosmic intelligence" which the Creator has put in the organism, and insists that it is impossible to deduce its purposive organization from its material constituents. In this he entirely overlooks the immense difference between the "raw material" in the two cases. The "organs" of the watch are metallic parts, which fulfil their purpose in virtue only of their physical properties (hardness, elasticity, etc.). The organs of the living organism, on the other hand, perform their functions chiefly in virtue of their chemical composition. Their soft plasma-body is a chemical laboratory, the highly elaborate molecular structure of which is the historical product of countless complicated processes of heredity and adaptation. This invisible and hypothetical molecular structure must not (as is often done) be confused with the real and microscopically discoverable structure of the plasm, which is of great importance in the questionof organization. If one is disposed to assume for this molecular structure a simple chemical substance, a deliberate design, and an "intelligent natural force" for cause, one is bound to do the same for powder, and say that the molecules of charcoal, sulphur, and saltpetre have been purposively combined to produce an explosion. It is well known that powder was not made according to a theory, but accidentally discovered in the course of experiment. The whole of this favorite machine-theory of life, and the far-reaching dualistic conclusions drawn from it, tumble to pieces when we study the simplest organisms known to us, the monera; for these are really organisms without organs—and without organization!
I endeavored in myGenerelle Morphologie(1866) to draw the attention of biologists to these simplest and lowest organisms which have no visible organization or composition from different organs. I therefore proposed to give them the general title of monera. The more I have studied these structureless beings—cells without nuclei!—since that time, the more I have felt their importance in solving the greatest questions of biology—the problem of the origin of life, the nature of life, and so on. Unfortunately, these primitive little beings are ignored or neglected by most biologists to-day. O. Hertwig devotes one page of his three-hundred-page book on cells and tissues to them; he doubts the existence of cells without nuclei. Reinke, who has himself shown the existence of unnucleated cells among the bacteria (beggiatoa), does not say a word about their general significance. Bütschli, who shares my monistic conception of life, and has given it considerable support by his own thorough study of plasma-structures and the artificial production of them in oil and soap-suds, believes, like many other writers, that the "composition of even the simplestelementary organism from cell-nucleus and protoplasm" (the primitive organs of the cell) is indispensable. These and other writers suppose that the nucleus has been overlooked in the protoplasm of the monera I have described. This may be true for one section of them; but they say nothing about the other section, in which the nucleus is certainly lacking. To this class belong the remarkablechromacea(phycochromaceaorcyanophycea), and especially the simplest forms of these, thechroococcacea(chroococcus,aphanocapsa,glœocapsa, etc.). These plasmodomous (plasma-forming) monera, which live at the very frontier of the organic and inorganic worlds, are by no means uncommon or particularly difficult to find; on the contrary, they are found everywhere, and are easy to observe. Yet they are generally ignored because they do not square with the prevailing dogma of the cell.
I ascribe this special significance to the chromacea among all the monera I have instanced because I take them to be the oldest phyletically, and the most primitive of all living organisms known to us. In particular their very simple forms correspond exactly to all the theoretic claims which monistic biology can make as to the transition from the inorganic to the organic. Of the chroococcacea, the chroococcus, glœocapsa, etc., are found throughout the world; they form thin, usually bluish-green coats or jelly-like deposits on damp rocks, stones, bark of trees, etc. When a small piece of this jelly is examined carefully under a powerful microscope, nothing is seen but thousands of tiny blue-green globules of plasma, distributed irregularly in the common structureless mass. In some species we can detect a thin structureless membrane enclosing the homogeneous particle of plasm; its origin can be explained on purely physical principles by "superficial energy"—like the firmer surface-layer of a drop of rain, or of a globule of oil swimmingin water. Other species secrete homogeneous jelly-like envelopes—a purely chemical process. In some of the chromacea the blue-green coloring matter (phyocyan) is stored in the surface-layer of the particle of plasm, while the inner part is colorless—a sort of "central body." However, the latter is by no means a real, chemically and morphologically distinct, nucleus. Such a thing is completely lacking. The whole life of these simple, motionless globules of plasm is confined to their metabolism (orplasmodomism, chapter x.) and the resulting growth. When the latter passes a certain stage, the homogeneous globule splits into two halves (like a drop of quicksilver when it falls). This simplest form of reproduction is shared by the chromacea (and the cognate bacteria) with the chromatella or chromatophora, the green particles of chlorophyll inside ordinary plant-cells; but these are only parts of a cell. Hence no unprejudiced observer can compare these unnucleated and independent granules of plasm with real (nucleated) cells, but must conceive them rather ascytodes. These anatomic and physiological facts may easily be observed in the chromacea, which are found everywhere. The organism of the simplest chromacea is really nothing more than a structureless globular particle of plasm; we cannot discover in them any composition of different organs (or organella) for definite vital functions. Such a composition or organization would have no meaning in this case, since the sole vital purpose of these plasma-particles is self-maintenance. This is attained in the simplest fashion for the individual by metabolism; for the species it is effected by self-cleavage, the simplest conceivable form of reproduction.
Modern histologists have discovered a very intricate and delicate structure in many of the higher unicellular protists and in many of the tissue-cells of the higheranimals and plants (such as the nerve-cells). They wrongly conclude that this is universal. In my opinion, this complication of the structure of the elementary organism is always a secondary phenomenon, the slow and gradual result of countless phylogenetic processes of differentiation, initiated by adaptation and transmitted to posterity by heredity. The earliest ancestors of all these elaborate nucleated cells were at first simple, unnucleated cytodes, such as we find to-day in the ubiquitous monera. We shall see more about them in the ninth and fifteenth chapters.
Naturally, this lack of a visible histological structure in the plasma-globule of the monera does not exclude the possession of an invisible molecular structure. On the contrary, we are bound to assume that there is such a structure, as in all albuminoid compounds, and especially all plasmic bodies. But we also find this elaborate chemical structure in many lifeless bodies; some of these, in fact, show a metabolism similar to that of the simplest organisms. We will return subsequently to this subject of catalysis. Briefly, the only difference between the simplest chromacea and inorganic bodies that have catalysis is in the special form of their metabolism, which we call plasmodomism (formation of plasm), or "carbon-assimilation." The mere fact that the chromacea assume a globular form is no sign whatever of a morphological vital process; drops of quicksilver and other inorganic fluids take the same shape when the individual body is formed under certain conditions. When a drop of oil falls into a fluid of the same specific gravity with which it cannot mix (such as a mixture of water and spirits of wine), it immediately assumes a globular shape. Inorganic solids usually take the form of crystals instead. Hence the distinctive feature of the simplest organism, the plasma-particles of the monera, is neither anatomic structure nor acertain shape, but solely the physiological function of plasmodomism—a process of chemical synthesis.
The difference between the monera I have described and any higher organism is, I think, greater in every respect than the difference between the organic monera and the inorganic crystals. Nay, even the difference between the unnucleated monera (as cytodes) and the real nucleated cells may fairly be regarded as greater still. Even in the simplest real cell we find the distinction between two different organella, or "cell-organs," the internal nucleus and the outer cell-body. Thecaryoplasmof the nucleus discharges the functions of reproduction and heredity; thecytoplasmof the cell-body accomplishes the metabolism, nutrition, and adaptation. Here we have, therefore, the first, oldest, and most important process of division of labor in the elementary organism. In the unicellular protists the organization rises in proportion to the differentiation of the various parts of the cell; in the tissue-forming histona it rises again in proportion to the distribution of work (or ergonomy) among the various organs. Darwin has given us in his theory of selection a mechanical explanation of the apparent design and purposiveness in this.
In order to have a correct monistic conception of organization, it is important to distinguish the individuality of the organism in its various stages of composition. We shall treat this important question, about which there is a good deal of obscurity and contradiction, in a special chapter (vii.). It suffices for the moment to point out that the unicellular beings (protists) are simple organisms both in regard to morphology and physiology. On the other hand, this is only true in the physiological sense of the histona, the tissue-forming animals and plants. From the morphological point of view they are made up of innumerable cells, which formthe various tissues. These histonal individuals are called sprouts in the plant world and persons in the animal world. At a still higher stage of organization we have the trunk or stem (cormus), which is made up of a number of sprouts or persons, like the tree or the coral-stem. In the fixed animal stems the associated individuals have a direct bodily connection, and take their food in common; but in the social aggregations of the higher animals it is the ideal link of common interest that unites the individuals, as in swarms of bees, colonies of ants, herds of mammals, etc. These communities are sometimes called "animal-states." Like human polities, they are organisms of a higher type.
However, in order to avoid misunderstanding, we must take the word "organism" in the sense in which most biologists use it—namely, to designate an individual living thing, the material substratum of which is plasm or "living substance"—a nitrogenous carbon-compound in a semi-fluid condition. It leads to a good deal of misunderstanding when separate functions are called organisms, as is done sometimes in speaking of the soul or of speech. It would be just as correct to call seeing or running an organism. It is advisable also in scientific treatises to refrain from calling inorganic compounds as such "organisms," as, for instance, the sea or the whole earth. Such names, having a purely symbolical value, may very well be used in poetry. The rhythmic wave-movement of the ocean may be regarded as its respiration, the surge as its voice, and so on. Many scientists (like Fechner) conceive the whole earth with all its organic and inorganic contents as a gigantic organism, whose countless organs have been arranged in an orderly whole by the world-reason (God). In the same way the physiologist, Preyer, regards the glowing heavenly bodies as "gigantic organisms, whose breath is, perhaps, the glowing vaporof iron, whose blood is liquid metal, and whose food may be meteorites." The danger of this poetic application of the metaphorical sense of organism is very well seen in this instance, as Preyer builds on it a quite untenable hypothesis of the origin of life (see chapter xv.).
In the wider sense the word "organic" has long been used in chemistry as an antithesis to inorganic. By organic chemistry is generally understood the chemistry of the compounds of carbon, that element being distinguished from all the others (some seventy-eight in number) by very important properties. It has, in the first place, the property of entering into an immense variety of combinations with other elements, and especially of uniting with oxygen, hydrogen, nitrogen, and sulphur to form the most complicated albuminoids (see theRiddle, chapter xiv.). Carbon is a biogenetic element of the first importance, as I explained in my carbon-theory in 1866. It might even be called "the creator of the organic world." At first these organogenetic compounds do not appear in the organism in organized form—that is to say, they are not yet distributed into organs with definite purposes. Such organization is a result, not the cause, of the life-process.
I have already shown in the fourteenth chapter of theRiddle(and at greater length in the fifteenth chapter of myHistory of Creation) that the belief in the essential unity of nature, or the monism of the cosmos, is of the greatest importance for our whole system. I gave a very thorough justification of this cosmic monism in 1866. In the fifth chapter of theGenerelle MorphologieI considered the relation of the organic to the inorganic in every respect, pointing out the differences between them on the one hand, and their points of agreement in matter, form, and force on the other. Nägeli some time afterwards declared similarly for the unity of nature in his ableMechanisch-physiologische Begründungder Abstammungslehre(1884). Wilhelm Ostwald has recently done the same, from the monistic point of view of his system of energy, in hisNaturphilosophie, especially in the sixteenth chapter. Without being acquainted with my earlier work, he has impartially compared the physico-chemical processes in the organic and inorganic worlds, partly adducing the same illustrations from the instructive field of crystallization. He came to the same monistic conclusions that I reached thirty-six years ago. As most biologists continue to ignore them, and as, especially, modern vitalism thrusts these inconvenient facts out of sight, I will give a brief summary once more of the chief points as regards the matter, form, and forces of bodies.
Chemical analysis shows that there are no elements present in organisms that are not found in inorganic bodies. The number of elements that cannot be further analyzed is now put at seventy-eight; but of these only the five organogenetic elements already mentioned which combine to form plasm—carbon, oxygen, hydrogen, nitrogen, and sulphur—are found invariably in living things. With these are generally (but not always) associated five other elements—phosphor, potassium, calcium, magnesium, and iron. Other elements may also be found in organisms; but there is not a single biological element that is not also found in the inorganic world. Hence the distinctive features which separate the one from the other can be sought only in some special form of combination of the elements. And it is carbon especially, the chief organic element, that by its peculiar affinity enters into the most diverse and complicated combinations with other elements, and produces the most important of all substances, the albuminoids, at the head of which is the living plasm (cf.chapter vi.).
An indispensable condition of the circulation of matter (metabolism) which we call life is the physical process ofosmosis, which is connected with the variations in the quantity of water in the living substance and its power of diffusion. The plasm, which is of a spongy or viscous consistency, can take in dissolved matter from without (endosmosis) and eject matter from within (exosmosis). This absorptive property (or "imbibition-energy") of the plasm is connected with the colloidal character of the albuminoids. As Graham has shown, we may divide all soluble substances into two groups in respect of their diosmosis—crystalloids and colloids. Crystalloids (such as soluble salt and sugar) pass more easily into water through a porous wall than colloids (such as albumen, glue, gum, caramel). Hence we can easily separate by dialysis two bodies of different groups which are mixed in a solution. For this we need a flat bottle with side walls of india-rubber and bottom of parchment. If we let this vessel float in a large one containing plenty of water, and pour a mixture of dissolved gum and sugar into the inner vessel, after a time nearly all the sugar passes through the parchment into the water, and an almost pure solution of gum remains in the bottle. This process of diffusion, or osmosis, plays a most important part in the life of all organisms; but it is by no means peculiar to the living substance, any more than the absorptive or viscous condition is. We may even have one and the same substance—either organic or inorganic—in both conditions, as crystal or as colloid. Albumen, which usually seems to be colloidal, forms hexagonal crystals in many plant-cells (for instance, in the aleuron-granules of the endosperm), and tetrahedric hœmoglobin-crystals in many animal-cells (as in the blood corpuscles of mammals). These albuminoid crystals are distinguished by their capacity for absorbing a considerable quantity of water without losing their shape. On the other hand, mineral silicon, which appears as quartz in an immense variety (more than one hundred and sixty)of crystalline forms, is capable in certain circumstances (as metasilicon) of becoming colloidal and forming jelly-like masses of glue. This fact is the more interesting because silicium behaves in other ways very like carbon, is quadrivalent like it, and forms very similar combinations. Amorphous (or non-crystalline) silicium (a brown powder) stands in relation to the black metallic silicon-crystals just as amorphous carbon does to graphite-crystals. There are other substances that may be either crystalloid or colloid in different circumstances. Hence, however important colloidal structure may be for the plasm and its metabolism, it can by no means be advanced as a distinctive feature of living matter.
Nor is it possible to assign an absolute distinction between the organic and the inorganic in respect of morphology any more than of chemistry. The instructive monera once more form a connecting bridge between the two realms. This is true both of the internal structure and the outward form of both classes of bodies—of their individuality (chapter vii.) and their type (chapter viii.). Inorganic crystals correspond morphologically to the simplest (unnucleated) forms of the organic cells. It is true that the great majority of organisms seem to be conspicuously different from inorganic bodies by the mere fact that they are made up of many different parts which they use as organs for definite purposes of life. But in the case of the monera there is no such organization. In the simplest cases (chromacea, bacteria) they are structureless, globular, discoid, or rod-shaped plasmic individuals, which accomplish their peculiar vital function (simple growth and subdivision) solely by means of their chemical constitution, or their invisible molecular structure.
The comparison of cells with crystals was made in 1838 by the founders of the cell-theory, Schleiden andSchwann. It has been much criticised by recent cytologists, and does not hold in all respects. Still it is of importance, as the crystal is the most perfect form of inorganic individuality, has a definite internal structure and outward form, and obtains these by a regular growth. The external form of crystals is prismatic, and bounded by straight surfaces which cut each other at certain angles. But the same form is seen in the skeletons of many of the protists, especially the flinty shells of the diatomes and radiolaria; their silicious coverings lend themselves to mathematical determination just as well as the inorganic crystals. Midway between the organic plasma-products and inorganic crystals we have thebio-crystals, which are formed by the united plastic action of the plasm and the mineral matter—for instance, the crystalline flint and chalk skeletons of many of the sponges, corals, etc. Further, by the orderly association of a number of crystals we get compound crystal groups, which may be compared to the communities of protists—for instance, the branching ice-flowers and ice-trees on the frozen window. To this regular external form of the crystal corresponds a definite internal structure which shows itself in their cleavage, their stratified build, their polar axes, etc.
If we do not restrict the term "life" to organisms properly so-called, and take it only as a function of plasm, we may speak in a broader sense of the life of crystals. This is seen especially in their growth, the phenomenon which Baer regarded as the chief character of all individual development. When a crystal is formed in a matrix, this is done by attracting homogeneous particles. When two different substances, A and B, are dissolved in a mixed and saturated solution, and a crystal of A is put in the mixture, only A is crystallized out of it, not B; on the other hand, if a crystal of B is put in, A remains in solution and B alone assumes thesolid crystalline form. We may, in a certain sense, call this choiceassimilation. In many crystals we can detect internally an interaction of their parts. When we cut off an angle in a forming crystal, the opposite angle is only imperfectly formed. A more important difference between the growth of crystals and monera is that the former only grow byapposition, or the deposit of fresh solid matter at their surface; while the monera grow, like all cells, byintussusception, or the taking of new matter into their interior. But this difference is easily explained by their difference in consistency, the crystal being solid and the plasm semi-fluid. Moreover, the difference is not absolute; there are intermediary stages between apposition and intussusception. A colloid globule suspended in a salt solution in which it is not dissolved may grow by intussusception.
It was once the custom to restrict sensation and movement to animals, but they are now recognized to be present in nearly all living matter. They are, in fact, not altogether lacking in crystals, as the molecules move in crystallization in definite directions, and unite according to fixed laws; they must, therefore, also possess sensation, as we could not otherwise understand the attraction of the homogeneous particles. We find in crystallization, as in every chemical process, certain movements which are unintelligible without sensation—unconscious sensation, of course. In this respect, also, then, the growth of all bodies follows the same laws (cf.chapters xiii. and xv.).
The growth of a crystal is restricted like the growth of a moneron or of any cell. If the limit is passed and the conditions remain favorable to growth, we find an instance of that excessive ortransgressivegrowth which we call reproduction in the case of living individuals. But we find just the same kind of extension in the inorganic crystal. Every crystal grows in a supersaturatedmedium only up to a definite size, which is determined by its chemical-molecular constitution. When this limit is reached a number of small crystals appear on the large one. Ostwald, who has made a thorough comparison of the process of growth in crystals and monera, especially notices the striking analogy between a bacterium (a plasmophagous moneron) growing and multiplying in its nutritive fluid and a crystal in its matrix. When the water slowly evaporates from a supersaturated solution of Glauber-salt, not only does a crystal slowly grow in it, but several young crystals appear on it. The analogy with the bacterium multiplying in its nutritive fluid can even be followed as far as its permanent forms or "spores." This quiescent form is assumed by the bacterium if its supply of food is exhausted; if fresh food is added, the multiplication by cleavage begins again. In the same way the crystals of Glauber-salt begin to decay when the solution is evaporated; they lose their crystal water, but not their power of multiplication. Even the amorphous powder of the salt causes again the formation of new watery crystals when put in a supersaturated solution. But the powder loses this property when it is heated, just as the dormant forms (or spores) of the bacteria lose their power of germination.
The exhaustive comparison of the growth of crystals and monera (as the simplest forms of unnucleated cells) is important, because it shows the possibility of tracing the vital function of reproduction—which had usually been regarded as a quite special "wonder of life"—to purely physical conditions. The division of the growing individual into several young ones must necessarily take place when the natural limit of growth has been passed, and when the chemical composition of the growing body and the cohesion of its molecules allow no further enlargement by the assumption of new matter. In orderto illustrate the limit of this transgressive growth by a simple physical example, Ostwald imagines a ball placed in a small flat basin, built up high on one side. The ball is in a state of equilibrium in the basin; when it is lightly pushed aside it always returns to its original position. But when the push goes beyond a certain point, and the ball is thrust over the side of the basin, the balance is lost; the ball does not return, but falls to the ground. The crystal behaves just in the same way in a supersaturated solution when it exercises its power of forming new crystals; and it is just the same with the bacterium growing in a nutritive fluid when it passes the limit of its volume of growth, and divides into two individuals.
As we can find no morphological and little physiological difference between the living and non-living, we must look upon metabolism as the chief characteristic of organic life. This process causes the conversion of food into plasm; it is determined by the vital force itself, and is the formation of new living matter. It thus effects the nutrition and growth of the living being, and therefore its reproduction, which is merely transgressive growth. As I shall describe this metabolism fully in the tenth chapter, I will do no more here than emphasize the fact that this vital process also has analogies in inorganic chemistry, in the curious process of catalysis, especially that form of it which we call fermentation.
The distinguished chemist Berzelius discovered in 1810 the remarkable fact that certain bodies, by their mere presence, apart from their chemical affinity, set other bodies in decomposition or composition without being themselves affected. Thus, for instance, sulphuric acid changes the starch in sugar without undergoing any alteration itself. Finely ground platinum brought in contact with hydrogen-superoxide divides it into hydrogen and oxygen. Berzelius called this processcatalysis; Mitscherlich, who discovered the cause of it to be the peculiar surface-action of many bodies, gave it the name of "contact-action." It was afterwards discovered that catalysis of this kind is very general, and that a special form of it—fermentation—plays an important part in the life of organisms.
This special form of contact-action which we call fermentation is always effected by catalytic bodies of the albuminoid class, and, in fact, of the group of non-coagulable proteins which are known as peptones. They have—in however small a quantity—the capacity to throw into decomposition large masses of organic matter (in the form of yeast, putrid matter, etc.) without themselves taking part in the decomposition. When these ferments are free and unorganized they are called enzyma, in opposition to organized ferments (bacteria, yeast-fungi, etc.); though the catalytic action of the latter also consists essentially in the production of enzyma. The recent investigations of Verworn, Hofmeister, Ostwald, etc., have shown that these catalyses play everywhere an important part in the life of the plasm. Many recent chemists and physiologists are of opinion that plasm is acolloid catalysator, and that all the varied activities of life are connected with this fundamental vital chemistry. Thus Franz Hofmeister (1901) says in his excellent work onThe Chemical Organization of the Cell:
The belief that the agents of the chemical transformation in the cell are catalysators of a colloid nature is in complete accord with other facts that have been directly ascertained. What else are the chemists' ferments but colloid catalysators? The idea that the ferments are the essential chemical agency in the cell is calculated to meet the difficulty which arises from the smallness of the cell in appreciating its chemical processes. However large we suppose the colloid ferment molecules to be, there is room for millions of them in the smallest cell.
In the same way Ostwald attributes the greatest significance to catalysis in connection with the vital processes, and seeks to explain them on his theory of energy by reference to the duration of chemical processes. In the discourse "On Catalysis" that he delivered at Hamburg in 1901 he says:
We must recognize the enzyma as catalysators that arise in the organism during the life of the cells, and by their action relieve the living being of the greater part of its duties. Not only are digestion and assimilation controlled by enzyma from first to last, but the fundamental vital action of most organisms, the production of the necessary chemical energy by combustion at the expense of the oxygen in the air, takes place with the explicit co-operation of enzyma, and would be impossible without them. Free oxygen is, as is well known, a very inert body at the temperature of the living body, and the maintenance of life would be impossible without some acceleration of its rate of reaction.
In his further observations on catalysis and metabolism he says that they are both equally subject to the physico-chemical laws of energy.
Max Verworn has given us a very searching analysis of the molecular process in the catalytic aspect of metabolism in hisBiogen Hypothesis(1903), "a critical and experimental study of the processes in living matter." He simplifies the catalytic theory of the enzyma by tracing all the phenomena of life to the catalytic metabolism of one single chemical compound, the plasm, and regards its active molecules, the biogens, as the ultimate chemical factors of the vital process. While the enzyma hypothesis assumes that there are in each cell a great number of different enzyma which are all co-ordinated, and each of which only performs its little special work, the biogen hypothesis deduces all the vital phenomena from one compound, the biogenetic plasm; and thus the biogen molecules, which increase by division into parts,are the sole factors of biological catalysis. Verworn also points out the analogy between this enzymatic process of metabolism and the inorganic processes of catalysis—for instance, in the manufacture of English sulphuric acid. A small and constant quantity of nitromuriatic acid, with the aid of air and water, converts an unlimited mass of sulphuretted acid into sulphuric acid without being changed itself; the molecule of the nitromuriatic acid breaks up steadily by the giving-off of oxygen, and is then restored by the assumption of oxygen.
The manifold and changeful phenomena of life and their sudden extinction at death seem to every thoughtful man to be something so wonderful and so different from all the changes in inorganic nature that from the very beginning of biological philosophy special forces were assumed to explain it. This was particularly due to the remarkable, orderly structure of the organism and the apparent purposiveness of the vital processes. Hence, in earlier days a special organic force (archæus insitus) was assumed, controlling the individual life and pressing the "raw forces" of inorganic matter into its service. In the same way a special formative impulse was supposed to preside over the wonderful processes of development. When physiology began to win its independence, about the middle of the eighteenth century, it explained the peculiar features of organic life by a specific vital force. The idea was generally received, and Louis Dumas endeavored thoroughly to establish it at the beginning of the nineteenth century (cf.chapter iii. of theRiddle).
As the theory of a vital force, or vitalism, plays an important part in the study of the wonders of life, has undergone the most curious modifications in the course of the nineteenth century, and has been lately revived with great force, we must give a short account of it in its various forms. The phrase can be interpreted in amonistic sense, if we understand by it the sum of the forms of energy which are especially distinctive of the organism, particularly metabolism and heredity. In this we pass no opinion on their nature, and do not say that they are specifically different from the forces of inorganic nature. We might call this monistic conception "physical vitalism." However, the usual metaphysical vitalism affirms in a thoroughly dualistic sense that the vital force is a teleological and super-mechanical principle, is essentially different from the ordinary forces of nature, and of a transcendental character. The special form in which this theory of a supernatural vital force has been presented for the last twenty years is often called Neovitalism; we might call the older form, by contrast, Palavitalism.
The older idea of the vital force as a special energy could very well be accepted in the first third of the nineteenth century, and in the eighteenth, because the physiology of the time was destitute of the most important aids to the founding of a mechanical theory. There was then no such thing as the cell-theory or as physiological chemistry; ontogeny and paleontology were still in their cradles. Lamarck's theory of descent (1809) had been done to death, like his fundamental principle: "Life is only an elaborate physical phenomenon." Hence we can easily understand how physiologists acquiesced in the vitalist hypothesis up to 1833, and supposed the wonders of life to be enigmatic phenomena that escaped physical explanation.
But the position of Palavitalism changed in the second third of the nineteenth century. In 1833 appeared Johannes Müller's classicalManual of Human Physiology, in which the great biologist not only made a comparative study of the vital phenomena in man and the animals, but sought to provide a sound basis for it in all its sections by his own observations and experiments. Itis true that Müller retained to the last (1858) the current idea of a vital force, as the supreme regulator of all the vital activities. However, he did not regard it as a metaphysical principle (like Haller, Kant, and their followers), but as a natural force, subject, like all others, to fixed chemical and physical laws, and subordinate to the whole. In his comprehensive study of every single vital function—the organs of sense and the nervous system, metabolism and the action of the heart, speech and reproduction—Müller endeavored above all to establish, by close observation of the facts and careful experiments, the regularity of the phenomena, and to explain their development by a comparison of the higher and lower forms. Hence Johannes Müller is wrongly described—as he has been of late—as a vitalist; he was rather the first physiologist to provide a physical foundation for the current metaphysical vitalism. He really gives an indirect proof of the reverse theory, as E. Dubois-Reymond rightly observed in his brilliant memorial speech. In the same way Schleiden (1843) cut the ground from under vitalism in botany. By his cell-theory (1838) he showed the unity of the multicellular organism to be the resultant of the functions of all the cells which compose it.
The physical explanation of the vital processes and the rejection of Palavitalism were general in the last third of the nineteenth century. This was due most of all to the great advance in experimental physiology, which Carl Ludwig and Felix Bernard led as regards the animal body, and Julius Sachs and Wilhelm Preyer for the plant. While these and other physiologists used the remarkable results of modern physics and chemistry in the experimental study of the vital functions, and sought to determine their complicated course in terms of mass and weight and formulate their discoveries as mathematically as possible, they brought agreat number of the wonders of life under the same fixed laws that were recognized in the physics and chemistry of the inorganic world. On the other hand, vitalism met with a powerful opponent in Charles Darwin, who solved, by his theory of selection, one of the most obscure biological problems, the constantly repeated question: How can we give a mechanical explanation of the orderly structures of the living being? How was this ingenious machine of the animal or plant body unconsciously produced by natural means, without supposing that some intelligent artificer or creator had deliberately designed and produced it?
The further development of Darwin's theory of selection in the last four decades, and the increasing support which has been given to the theory of descent in the great advance of ontogeny, phylogeny, comparative anatomy, and physiology, did much to establish the monistic conception of life. It took the shape more and more of a definite anti-vitalism. Hence it is strange to find that in the course of the last twenty years the old vitalism that everybody had thought dead has lifted up its head once more, though in a new and modified form.[4]This modern vitalism comprises two essentially different tendencies.
The partisans of the modern vital force are divided into two groups, which may be designated the sceptical and the dogmatic. Sceptical Neovitalism was first formulated by Bunge, of Basle (1887), in the introduction to hisManual of Physiological Chemistry. While hegranted the possibility of a full explanation of one part of the vital phenomena by mechanical causes, or the physical and chemical forces of lifeless nature, he rejected it for the other half, especially for psychic activities. He insists that the latter cannot be explained mechanically, and that there is nothing analogous to them in inorganic nature; only a supra-mechanical vital force can produce them, and this is transcendental and beyond the range of scientific inquiry. Much the same was said later by Rindfleisch (1888), more recently by Richard Neumeister in hisStudies of the Nature of Vital Phenomena(1903), and by Oscar Hertwig in the lecture on "The Development of Biology in the Nineteenth Century," which he delivered at Aachen in 1900.
This sceptical Neovitalism is far surpassed by the dogmatic system, the chief actual representatives of which are the botanist Johannes Reinke and the metaphysician Hans Driesch. The vitalist writings of the latter, which are devoid of any grasp of historical development, have gained a certain vogue through the extraordinary arrogance of their author and the obscurity of his mystic and contradictory speculations. Reinke, on the other hand, has presented his transcendental dualism in clever and attractive form in two works which deserve notice on account of their consistent dualism. In the first of these,The World as Reality(1899), Reinke gives us "the outline of a scientific theory of the universe." The second work (1901) has the title,Introduction to Theoretical Biology. The two works have the same relation to each other as myRiddle of the Universeand the present supplementary volume. As our philosophic convictions are diametrically opposed in the main issues, and as we both think ourselves consistent in developing them, the comparison of them is not without interest in the great struggle of beliefs. Reinke is anavowed supporter of dualism, theism, and teleology. He reduces all the phenomena of life to a supernatural miracle.
Second Table
ANTITHESIS OF THE MONISTIC AND DUALISTIC THEORIES OF ORGANIC LIFE
III
Miracle and natural law—Belief in miracles of savages (fetichism), of semi-civilized (idolatry), of civilized (theism), and of educated people (dualism)—Religious belief in miracles—Apostles' Creed—Article relating to creation—Article relating to redemption—Article relating to immortality—Philosophic belief in miracles—Academic thinkers and Free-thinkers—Dualism of Plato and Kant—Belief in miracles in the nineteenth century, in modern metaphysics, theology, and politics.
In ordinary parlance the word "miracle" means a number of different things. We say a phenomenon is miraculous or wonderful[5]when we cannot explain it and trace its causes. But we say a natural object or a work of art is wonderful when it is unusually beautiful and imposing—when it passes the ordinary limits of our experience. In this work I do not take the word in this relative sense, but in the absolute sense in which a phenomenon is said to transcend the limits of natural law and lie beyond the range of rational explanation. In this sense it means the same as "supernatural" or "transcendental." We can know natural phenomena by our reason and bring them within our cognizance. The miraculous can only be accepted on faith.
The belief in supernatural miracles is in contradiction to pure reason, which lays the foundations of all science. Kant, who won so great a vogue for the term "pure reason," understood by this originally "reason as independent of experience." The phrase was used in a narrower sense subsequently to express independence of dogma and prejudice, as the base of pure and unprejudiced science. In this sense we oppose pure reason to superstition.
I have dealt in the sixteenth chapter of theRiddlewith the important question of the relations of knowledge and faith. But I must return to the subject here, as what I said has given rise to a good deal of misunderstanding and criticism. I by no means claimed, as my opponents allege, to "know everything," or to have solved every problem. In fact, I said repeatedly that there are narrow limits to our knowledge, and always will be. I had also expressly stated that the irresistible impulse to learn in the intelligent man, or reason's constant demand to know causes, presses us to fill up the gaps in our knowledge by faith. But I had at the same time pointed out the contrast between scientific (natural) and religious (supernatural) faith. The one leads us to form hypotheses and theories; the other ends in myths and superstition. Scientific faith fills the gaps in our knowledge of natural law with temporary hypotheses; but mystic religious faith contradicts natural law, and transcends its limits in the form of a belief in miracles.
The great triumph of the progress of science in the nineteenth century, its theoretical value in the formation of a rational philosophy of life, and its practical value on the various sides of modern civilization, consist, above all, in the absolute recognition of fixed natural laws. That relation of things to each other, which we call causation, makes it possible for us to understand and explain facts. We feel that our thirst for a knowledgeof the causes of things is contented when science points out the "sufficient reason" of them. In the whole province of inorganic cosmology natural law is now generally recognized to be all-powerful; in astronomy, geology, physics, and chemistry all phenomena are reduced to fixed laws, and in the long-run to the all-embracing law of substance, the great law of the conservation of matter and force (Riddle, chapter xii.).
It is otherwise in biology, or the organic section of cosmology. Here we still find miracles set up in opposition to the law of substance, and the transgression of natural laws by supernatural forces. The belief in miracles of this kind, which pure reason calls superstition, is still very wide-spread—much more prevalent than is usually thought. For my part, I hold that superstition and unreason are the worst enemies of the human race, while science and reason are its greatest friends. Hence it is our duty and task to attack the belief in miracles wherever we find it, in the interest of the race. We have to prove that the reign of natural law extends over the whole world of phenomena as far as we can reach it. A general survey of the history of faith on the one hand and of science on the other clearly shows that the advance of the latter has always been accompanied by an increasing knowledge of fixed natural laws and the shrinking of superstition into an ever-lessening area. To-day we convince ourselves of this by an impartial examination of mental culture at the various stages of civilization. For this purpose I take the four chief stages of mental development which Fritz Schultze has given in hisPhysiology of Uncivilized Races, and Alexander Sutherland in his work,On the Origin and Growth of the Moral Instinct: 1, savages; 2, barbarians; 3, civilized races; 4, educated races (cf.chapter i.).
The mental life of savages rises little above thatof the higher mammals, especially the apes, with which they are genealogically connected. Their whole interest is restricted to the physiological functions of nutrition and reproduction, or the satisfaction of hunger and thirst in the crudest animal fashion. Without fixed habitation, constantly struggling for existence, they live on the raw produce of nature—fruits, the roots of wild plants, and the animals they fish in the water or catch on land. Their intelligence moves within the narrowest bounds, and one can no more (or no less) speak of their reason than of that of the more intelligent animals. Of art and science there is no question. Their impulse to discover causes is satisfied with the simplest association of phenomena which have a merely external connection, but no intimate relation to each other. Thus arises theirfetichism, that irrational trust in fetiches which Fritz Schultze has traced to four distinct causes: their false estimate of the value of an object, their anthropomorphic conception of nature, the imperfect association of their ideas, and the strength of their emotions, especially hope and fear. Any favorite object, a stone or a bone, may work miracles as a fetich and exercise all kinds of good or evil influence, and is therefore honored, feared, and worshipped. At first the worship was paid to the invisible spirit that dwelt in the particular object; but it was often transferred afterwards to the dead object itself. Among the different savage races the belief in fetiches presents a number of stages, corresponding to the beginnings of reason. The lowest stage is found in the lowest races, such as the Veddahs of Ceylon, the Andaman Islanders, Bushmen, and Akkas (of New Guinea). A somewhat higher stage is met in the middle races (Australian negroes, Tasmanians, Hottentots, and Tierra del Fuegians); and a still higher intellectual development is shown by the next group (most of the Indians of North and South America, the aboriginalinhabitants of India, etc.). Modern comparative ethnography and evolution and prehistoric and anthropological research have shown us that our own ancestors, ten thousand and more years ago, were (like the prehistoric ancestors of all races of men) savages, and that their earliest belief in miracles was a crude fetichism.
By barbarians we understand the races that are found between savage and civilized peoples. They show the first beginnings of civilization, and are superior to savages chiefly in the possession of agriculture and the keeping of cattle. They make a provident use of the productive forces of organic nature, artificially produce large quantities of food, and are thus enabled by the abundance of food to turn their minds to other interests. We find that they have the rudiments of art and science. Their religion does not at first rise much above fetichism, but soon reaches the stage of animism, lifeless objects in nature being credited with souls. Worship is no longer paid to favorite dead objects (stones, bones, etc.), but generally to living things, trees and animals, and especially to images of gods which have the form of animals or men, and are believed to possess souls. As demons or spirits, these have a great influence on the fortunes of men. At first this soul is conceived to be purely material; it disappears at the death of the body and lives apart. As the breathing and the beat of the pulse and heart cease when a man dies, the seat of the soul is thought to be the lungs, heart, or some other part of the body. The idea of the immortality of the soul takes on innumerable forms among them, like the belief in the miracles which are worked by the gods, demons, spirits, etc. Evolution again points out a long gradation of forms of faith, if we compare the lower, middle, and higher races.
Civilized races are distinguished from barbaric by the formation of states with an extensive division of labor.The social organism is not only larger and more powerful, but is capable of a greater variety of achievements, the functions of the various states and classes of workers being more highly differentiated and mutually complementary (like the cells and tissues in the higher animal body of the metazoa). Nutrition is easier and more luxurious. Art and science are well developed. A great advance is seen in regard to religion, the numerous gods being generally conceived as manlike spirits, and finally subordinated to a chief god. The belief in miracles flourishes greatly in poetry; in philosophy it is more and more restricted. In the end, the working of miracles is limited monotheistically to one god, or to his priests and other men to whom he communicates the power.
Modern civilization in the narrower sense, as a contrast to the older civilization, opens, in my opinion, at the beginning of the sixteenth century. At that time took place some of the greatest achievements of human thought among civilized peoples, and these broke the chains of tradition and gave a fresh impetus to progress. Men's own mental outlook was widened by the system of Copernicus and the Reformation freed them from the yoke of the papacy. Shortly before, the discovery of the New World and the circumnavigation of the globe had convinced men of the rotundity of the earth; geography, natural history, medicine, and other sciences gained inspiration and independence; printing and engraving provided an important means of spreading the new knowledge. This fresh impetus was chiefly of service to philosophy, which now more and more rejected the dictation of the Church and superstition; though it was far from casting off the fetters altogether. This was not generally possible until the nineteenth century, when empirical science assumed an enormous importance, and in the ensuing period of speculation the physical conceptionof the world gained more and more on the metaphysical. Pure knowledge, thus grounded on science, entered into sharper conflict than ever with religious faith. If, as in the preceding cases, we distinguish three stages in the development of modern civilization, we recognize the progressive liberation from superstition by scientific knowledge.
When we compare the higher forms of religion of civilized nations we find the same emotional cravings and thought-processes constantly recurring, and the belief in miracles developing in much the same way. The three founders of the great monotheistic Mediterranean religion—Moses, Christ, and Mohammed—were equally regarded as wonder-working prophets, having direct intercourse with God in virtue of their special gifts, and transmitting his commands to men in the shape of laws. The extraordinary authority they enjoy, which has given so much prestige to the religions they founded, is grounded for ordinary people on their miraculous powers—the healing of the sick, the raising of the dead, the expulsion of devils, and so on. If we examine the miracles of Christ as they are given in the gospels, they run counter to the laws of nature and rational explanation just in the same way as the similar miracles of Buddha and Brahma in Hindoo mythology, or of Mohammed in the Koran. The same must be said of the belief in the miracle of the bread and wine in the Lord's supper, and the like. The Creed which was probably drawn up by the leaders of the Christian communities of the second century, and received its final and present form in the Church of South Gaul in the fourth and fifth centuries, has been obligatory for Christians for fifteen hundred years, and recognized by both Church and State as compulsory. This Apostles' Creed was also recognized in Luther's catechism to be fundamental, and is taught in all Protestant and RomanCatholic schools (though not in the Greek Catholic) as the foundation of religious instruction. This extraordinary prestige of the Apostles' Creed, and its great influence on the education of the young, no less than its glaring inconsistency with rational knowledge, compel us to devote a few pages to a critical examination of its three articles.
The first article of the Creed deals with creation, and runs: "I believe in God, the Father Almighty, Creator of heaven and earth." The modern science of evolution has shown that there never was any such creation, but that the universe is eternal and the law of substance all-ruling. God himself is anthropomorphically conceived as an "Almighty Creator" and the Father of man; heaven (in the sense of the geocentric system) is imagined as a great blue vault spanning the earth. The notion of this "personal God" as an intelligent, immaterial being, creating the material world out of nothing, is wholly irrational and meaningless. That Luther accepted this childish and scientifically worthless idea is clear from his commentary on the first article—"What is that?"
The second article of the Creed deals with the dogma of salvation in the following words: "I believe in Jesus Christ, his only son, our Lord, who was conceived of the Holy Ghost, born of the Virgin Mary, suffered under Pontius Pilate, was crucified, dead, and buried, descended into hell, on the third day rose again from the dead, ascended into heaven, sitteth at the right hand of God, the Father Almighty, whence he will come to judge the living and the dead." As these dogmas of the second article contain the chief points of the redemption theory, and are still treasured by millions of educated people, it is necessary to point out their flagrant opposition to pure reason. The chief evil of such creeds is that children, who are yet incapable of reflecting, are forced to learnthem by heart. They then remain unchallenged as revealed truths.
The myth of the conception and birth of Jesus Christ is mere fiction, and is at the same stage of superstition as a hundred other myths of other religions. Of the three persons who are mysteriously blended in the triune God, the son Christ is supposed to be begotten by both Father and Holy Ghost, parthenogenetically through the Virgin Mary. I have dealt with the physiology of parthenogenesis in the seventeenth chapter of theRiddle. The curious adventures of Christ after his death, the descent into hell, resurrection, and ascension, are also fantastic myths due to the narrow geocentric ideas of an uneducated people. Troelslund has admirably explained the strong influence they have had in his interesting book,The Idea of Heaven and of the World.[6]The idea of the "last judgment," with Christ sitting on the right hand of the Father, as many famous mediæval pictures represent (notably Michael Angelo's in the Sistine Chapel at the Vatican), is another outcome of a thoroughly childish and anthropomorphic attitude.
It is remarkable that this second article of the Creed says nothing about "redemption," which forms its heading [in Germany]. Luther has dealt with it in his commentary. Christ is believed to have suffered a painful death, like many thousand other martyrs, for his conviction of the truth of his faith and teaching—which reminds one of the more than a hundred thousand men who were done to death by the Inquisition and in the religious wars of the Middle Ages; but not one of themillions of ministers who preach on it every Sunday seems to have shown a rational causal connection of this death with the alleged redemption from sin and death. The whole of this story of redemption has sprung from the primitive, obscure, ethical ideas of uneducated races, especially the crude belief in the propitiatory power of human sacrifice. It has no practical moral value except for those who believe in personal immortality—a scientifically untenable dogma. Whoever builds on this empty promise of a better life beyond may soothe himself with this hope, and reconcile himself to the thousand ills and defects of this world. But the man who studies this life as it really is will not find that the belief in redemption has brought any real improvement. Want and misery and sin are as prevalent as ever; indeed, our modern civilization has, in many respects, increased them.
The third and last article of the Apostles' Creed runs: "I believe in the Holy Ghost, the holy Catholic Church, the communion of saints, the forgiveness of sins, the resurrection of the body, and life everlasting." In the curious commentary that Luther made on this article in his catechism, he said that "man cannot believe of his own reason in Jesus Christ"—which is very true—but the Holy Ghost must lead him thereto with his grace; but how the third person of the Trinity effects this enlightenment and sanctification he did not explain. What is meant by the "communion of saints" and the "holy Catholic Church" must be gathered in the light of their history—especially the history of Romanism. This most powerful and still influential section of the Christian Church, which especially claims the title of Catholic and "the one ark of salvation," is really a most pitiful caricature of pure primitive Christianity. It has, with consummate skill, succeeded in preaching the beneficent teaching of Christ in theory and doing just the oppositein practice; we need only recall the Inquisition, the dark history of the Middle Ages, and the political hierarchy which still dominates so much of civilization.
However, by far the most important clause in the third article is the final expression of belief in "the resurrection of the body and life everlasting." That this greatest "wonder of life" was originally conceived in a purely material form is evident from thousands of pictures in which famous painters have realistically depicted the resurrection of the dead, the aërial flight of the happy souls of the blessed, and the torments of the damned in hell. It is thus conceived still by the majority of believers who take eternal life to be an "enlarged and improved edition" of life here below. This is equally true of Christian and Mohammedan pictures and of the athanatist ideas that prevailed in other religions long before Christ was born, even of the first rudiments of the belief in primitive races. As long as the geocentric theory prevailed, and the heavens were thought to be a sort of blue glass bell, illumined by thousands of little stars and the lamp of the sun, arching like a vault over the flat earth, and the fires of hell burned in the cellars below, this barbaric notion of a resurrection of the body and a last judgment could easily be maintained. But its roots were destroyed when Copernicus refuted the geocentric theory in 1545; and athanatism became quite untenable when Darwin shattered the dogma of anthropocentricism. Not only the crude older materialistic idea of eternal life, but also the refined new spiritualistic version, has been rendered untenable by the progress of science in the nineteenth century. I have shown this in the eleventh chapter of theRiddle, which closes with the words: "If we take a comprehensive glance at all that modern anthropology, psychology, and cosmology teach with regard to athanatism, we are forced to this definite conclusion. The belief in the immortality of the humansoul is in hopeless contradiction with the most solid empirical truths of modern science."[7]
The great influence which has been exercised on civilized nations by the Christian beliefs, supported by the practical exigencies of the state, for thousands of years, was chiefly seen in the crude superstition of the mass of the people. Confessions of faith became as much a matter of routine as the latest fashion in dress or the latest custom, etc. But even the majority of the philosophers were more or less subordinated to the influence. It is true that a few great thinkers freed themselves by the use of pure reason at an early date from the prevalent superstition, and framed systems apart from tradition and the priests. But most philosophers could not rise to the altitude of these brave Free-thinkers; they remained "school-men" in the literal sense, dependent on the dictation of authority, the traditions of the school, and the dogmas of the Church. Philosophy was the "handmaid" of theology and ecclesiasticism. If we examine the history of philosophy in this light, we find in it a struggle for twenty-five hundred years between two great tendencies—the dualism of the majority (with theological and mystic leanings) and the monism of the minority (with rationalistic and naturalistic disposition).
Especially notable are those great Free-thinkers of classic antiquity who taught a monistic view of life in the sixth century before Christ—the Ionic natural philosophers, Thales, Anaximander, and Anaximenes; and a little later, Heraclitus, Empedocles, and Democritus. They made the first thorough attempt to explain the world on rational principles, independently of all mythological tradition and theological dogmas. However,these remarkable efforts to found a primitive monism, which found so finished an expression in theDe rerum naturaof the great poet-philosopher, Lucretius Carus (98-54B.C.), were shortly thrust out by the spread—through Plato's curious dualism—of the belief in the immortality of the soul and the transcendental world of ideas.
The Eleatics, Parmenides and Zeno, had foreshadowed in the fifth century the division of philosophy into two branches; but Plato and his pupil Aristotle (in the fourth centuryB.C.) succeeded in gaining general acceptance for this dualism and antithesis of physics and metaphysics. Physics devoted itself on the ground of experience to the study of the phenomena of things, leaving their real essences (or noumena) that lay behind the phenomena to metaphysics. These inner essences are transcendental and inaccessible to empirical research; they form the metaphysical world of eternal ideas, which is independent of the real world, and has its highest unity in God, as the Absolute. The soul, an eternal idea that dwells for a time in the passing human body, is immortal. This consistent dualism of Plato's system, with its sharp antithesis of this world and the next, of body and soul, of world and God, is its chief characteristic. It became all the more influential when Plato's pupil Aristotle blended it with his empirical metaphysics, based on ample scientific experience, and pointed out the idea in the entelechy, or purposively acting principle, of every being; and especially when Christianity (three hundred years afterwards) found in this dualism a welcome philosophic support of its own transcendental tendency.