[#] This simple expression acquires a mysterious appearance in mediæval philosophy from the standing mistranslationnotiora naturæ, "better known to nature."It follows that Aristotle, after all, admits the disparateness of sense-perception and scientific knowledge. Sense-perception of itself never gives us scientific truth, because it can only assure us that a fact is so; it cannotexplainthe fact by showing its connection with the rest of the system of facts, "it does not give thereasonfor the fact." Knowledge of perception is always "immediate," and for that very reason is never scientific. If we stood on the moon and saw the earth, interposing between us and the sun, we should still not have scientific knowledge about the eclipse, because "we should still have to ask for thereason why." (In fact, we should not know the reasonwhywithout a theory of light including the proposition that light-waves are propagated in straight lines and several others.) Similarly Aristotle insists that Induction does not yield scientific truth. "He who makes an induction points out something, but does not demonstrate anything."For instance, if we know thateachspecies of animal which is without a gall is long-lived, we may make the induction thatallanimals without a gall are long-lived, but in doing so we have got no nearer to seeingwhyorhowthe absence of a gall makes for longevity. The question which we may raise in science may all be reduced to four heads, (1) Does this thing exist? (2) Does this event occur? (3) If the thing exists, precisely what is it? and (4) If the event occurs,whydoes it occur? and science has not completed its task unless it can advance from the solution of the first two questions to that of the latter two. Science is no mere catalogue of things and events, it consists of inquiries into the "real essences" and characteristics of things and the laws of connection between events.Looking at scientific reasoning, then, from the point of view of its formal character, we may say that all science consists in the search for "middle terms" of syllogisms, by which to connect the truth which appears as a conclusion with the less complex truths which appear as the premisses from which it is drawn. When we ask, "does such a thing exist?" or "does such an event happen?" we are asking, "is there a middle term which can connect the thing or event in question with the rest of known reality?" Since it is a rule of the syllogism that the middle term must be taken universally, at least once in the premisses, the search for middle terms may also be described as the search for universals, and we may speak of science as knowledge of the universal interconnections between facts and events.A science, then, may be analysed into three constituents. These are: (1) a determinate class of objects which form the subject-matter of its inquiries. In an orderly exhibition of the contents of the science, these appear, as in Euclid, as the initial data about which the science reasons; (2) a number of principles, postulates, and axioms, from which our demonstrations must start. Some of these will be principles employed in all scientific reasoning. Others will be specific to the subject-matter with which a particular science is concerned; (3) certain characteristics of the objects under study which can be shown by means of our axioms and postulates to follow from our initial definitions, theaccidentia per seof the objects defined. It is these last which are expressed by the conclusions of scientific demonstration. We are said to know scientifically that B is true of A when we show that this follows, in virtue of the principles of some science, from the initial definition of A. Thus if we convinced ourselves that the sum of the angles of a plane triangle is equal to two right angles by measurement, we could not be said to have scientific knowledge of the proposition. But if we show that the same proposition follows from the definition of a plane triangle by repeated applications of admitted axioms or postulates of geometry, our knowledge is genuinely scientific. We now know that it is so, and we seewhyit is so; we see the connection of this truth with the simple initial truths of geometry.This leads us to the consideration of the most characteristic point of Aristotle's whole theory. Science is demonstrated knowledge, that is, it is the knowledge that certain truths follow from still simpler truths. Hence the simplest of all the truths of any science cannot themselves be capable of being known by inference. You cannot infer that the axioms of geometry are true because its conclusions are true, since the truth of the conclusions is itself a consequence of the truth of the axioms. Nor yet must you ask for demonstration of the axioms as consequences of still simpler premisses, because if all truths can be proved, they ought to be proved, and you would therefore require an infinity of successive demonstrations to prove anything whatever. But under such conditions all knowledge of demonstrated truth would be impossible. The first principles of any science must therefore be indemonstrable. They must be known, as facts of sense-perception are known, immediately and not mediately. How then do we come by our knowledge of them? Aristotle's answer to this question appears at first sight curiously contradictory. He seems to say that these simplest truths are apprehended intuitively, or on inspection, as self-evident by Intelligence or Mind. On the other hand, he also says that they are knownto usas a result of induction from sense-experience. Thus heseemsto be either a Platonist or an empiricist, according as you choose to remember one set of his utterances or another, and this apparent inconsistency has led to his authority being claimed in their favour by thinkers of the most widely different types. But more careful study will show that the seeming confusion is due to the fact that he tries to combine in one statement his answers to two quite different questions, (1) how we come to reflect on the axioms, (2) what evidence there is for their truth. To the first question he replies, "by induction from experience," and so far he might seem to be a precursor of John Stuart Mill. Successive repetitions of the same sense-perceptions give rise to a single experience, and it is by reflection on experience that we become aware of the most ultimate simple and universal principles. We might illustrate his point by considering how the thought that two and two are four may be brought before a child's mind. We might first take two apples, and two other apples and set the child to count them. By repeating the process with different apples we may teach the child to dissociate the result of the counting from the particular apples employed, and to advance to the thought, "any two apples and any two other apples make four apples." Then we might substitute pears or cherries for the apples, so as to suggest the thought, "two fruits and two fruits make four fruits." And by similar methods we should in the end evoke the thought, "any two objects whatever and any other two objects whatever make four objects." This exactly illustrates Aristotle's conception of the function of induction, or comparison of instances, in fixing attention on a universal principle of which one had not been conscious before the comparison was made.Now comes in the point where Aristotle differs wholly from all empiricists, later and earlier. Mill regards the instances produced in the induction as having a double function; they not merely fix the attention on the principle, they also are the evidence of its truth. This gives rise to the greatest difficulty in his whole logical theory. Induction by imperfect enumeration is pronounced to be (as it clearly is) fallacious, yet the principle of the uniformity of Nature which Mill regards as the ultimate premiss of all science, is itself supposed to be proved by this radically fallacious method. Aristotle avoids a similar inconsistency by holding that the sole function of the induction is to fix our attention on a principle which it does not prove. He holds that ultimate principles neither permit of nor require proof. When the induction has done its work in calling attention to the principle, you have to see for yourself that the principle is true. You see that it is true by immediate inspection just as in sense-perception you have to see that the colour before your eyes is red or blue. This is why Aristotle holds that the knowledge of the principles of science is not itself science (demonstrated knowledge), but what he calls intelligence, and we may call intellectual intuition. Thus his doctrine is sharply distinguished not only from empiricism (the doctrine that universal principles are proved by particular facts), but also from all theories of the Hegelian type which regard the principles and the facts as somehow reciprocally proving each other, and from the doctrine of some eminent modern logicians who hold that "self-evidence" is not required in the ultimate principles of science, as we are only concerned in logic with the question what consequences follow from our initial assumptions, and not with the truth or falsehood of the assumptions themselves.The result is that Aristotle does little more than repeat the Platonic view of the nature of science. Science consists of deductions from universal principles which sensible experience "suggests," but into which, as they are apprehended by a purely intellectual inspection, no sense-data enter as constituents. The apparent rejection of "transcendental moonshine" has, after all, led to nothing. The only difference between Plato and his scholar lies in the clearness of intellectual vision which Plato shows when he expressly maintains in plain words that the universals of exact science are not "in" our sense-perceptions and therefore to be extracted from them by a process of abstraction, but are "apart from" or "over" them, and form an ideal system of interconnected concepts which the experiences of sense merely "imitate" or make approximation to.One more point remains to be considered to complete our outline of the Aristotelian theory of knowledge. The sciences have "principles" which are discerned to be true by immediate inspection. But what if one man professes to see the self-evident truth of such an alleged principle, while another is doubtful of its truth, or even denies it? There can be no question of silencing the objector by a demonstration, since no genuine simple principle admits of demonstration. All that can be done,e.g.if a man doubts whether things equal to the same thing are equal to one another, or whether the law of contradiction is true, is to examine the consequences of a denial of the axiom and to show that they include some which are false, or which your antagonist at least considers false. In this way, by showing the falsity of consequences which follow from the denial of a given "principle," you indirectly establish its truth. Now reasoning of this kind differs from "science" precisely in the point that you take as your major premiss, not what you regard as true, but the opposite thesis of your antagonist, which you regard as false. Your object is not to prove a true conclusion but to show your opponent thathispremisses lead to false conclusions. This is "dialectical" reasoning in Aristotle's sense of the word,i.e.reasoning not from your own but from some one else's premisses. Hence the chief philosophical importance which Aristotle ascribes to "dialectic" is that it provides a method of defending the undemonstrable axioms against objections. Dialectic of this kind became highly important in the mediæval Aristotelianism of the schoolmen, with whom it became a regular method, as may be seene.g.in theSummaof St. Thomas, to begin their consideration of a doctrine by a preliminary rehearsal of all the arguments they could find or devise against the conclusion they meant to adopt. Thus the first division of any article in theSumma Theologiæof Thomas is regularly constituted by arguments based on the premisses of actual or possible antagonists, and is strictly dialectical. (To be quite accurate Aristotle should, of course, have observed that this dialectical method of defending a principle becomes useless in the case of a logical axiom which is presupposed by all deduction. For this reason Aristotle falls into fallacy when he tries to defend the law of contradiction by dialectic. It is true that if the law be denied, then any and every predicate may be indifferently ascribed to any subject. But until the law of contradiction has been admitted, you have no right to regard it as absurd to ascribe all predicates indiscriminately to all subjects. Thus, it is only assumed laws which arenotultimate laws of logic that admit of dialectical justification. If a truth is so ultimate that it has either to be recognised by direct inspection or not at all, there can be no arguing at all with one who cannot or will not see it.)CHAPTER IIIFIRST PHILOSOPHYFirst Philosophy is defined by Aristotle as a "science which considers What Is simply in its character of Being, and the properties which it has as such." That there is, or ought to be, such a science is urged on the ground that every "special" science deals only with some restricted department of what is, and thus considers its subject-matter not universally in its character of being, or being real, but as determined by some more special condition. Thus, First Philosophy, the science which attempts to discover the most ultimate reasons of, or grounds for, the character of things in general cannot be identified with any of the "departmental" sciences. The same consideration explains why it is "First Philosophy" which has to disentangle the "principles" of the various sciences, and defend them by dialectic against those who impugn them. It is no part of the duty of a geometer or a physicist to deal with objections to such universal principles of reasoning as the law of contradiction. They may safely assume such principles; if they are attacked, it is not by specifically geometrical or physical considerations that they can be defended. Even the "principles of the special sciences" have not to be examined and defended by the special sciences. They are the starting-points of the sciences which employ them; these sciences are therefore justified in requiring that they shall be admitted as a condition of geometrical, or physical, or biological demonstrations. If they are called in question, the defence of them is the business of logic.First Philosophy, then, is the study of "What Is simply as such," the universal principles of structure without which there could be no ordered system of knowable objects. But the word "is" has more than one sense. There are as many modes of being as there are types of predication. "Substances," men, horses, and the like, have their own specific mode of being--they are things; qualities, such as green or sweet, have a different mode of being--they are not things, but "affections" or "attributes" of things. Actions, again, such as building, killing, are neither things nor yet "affections" of things; their mode of being is that they are processes which produce or destroy things. First Philosophy is concerned with the general character of all these modes of being, but it is specially concerned with that mode of being which belongs tosubstances. For this is the most primary of all modes of being. We had to introduce a reference to it in our attempt to say what the mode of being of qualities and actions is, and it would have been the same had our illustrations been drawn from any other "categories." Hence the central and special problem of First Philosophy is to analyse the notion of substance and to show the causes of the existence of substances.Next, we have to note that the word "substance" itself has two senses. When we spoke of substance as one of the categories we were using it in a secondary sense. We meant by substances "horse," "man," and the rest of the "real kinds" which we find in Nature, and try to reproduce in a scientific classification. In this sense of the word "substances" are a special class ofpredicates, as when we affirm of Plato that he is a man, or of Bucephalus that he is a horse. But in the primary sense a substance means an absolutely individual thing, "thisman," or "thishorse." We may therefore define primary substances from the logician's point of view by saying that they can be only subjects of predication, never predicates. Or again, it is peculiar to substances, that while remaining numerically one a substance admits of incompatible determinations, as Socrates, remaining one and the same Socrates, is successively young and old. This is not true of "qualities," "actions," and the rest. The same colour cannot be first white and then black; the same act cannot be first bad and then good. Thus we may say that individual substances are the fixed and permanent factors in the world of mutability, the invariants of existence. Processes go on in them, they run the gamut of changes from birth to decay, processes take placeamongthem, they act on and are acted on by one another, they fluctuate in their qualities and their magnitude, but so long as a substance exists it remains numerically one and the same throughout all these changes. Their existence is the first and most fundamental condition of the existence of the universe, since they are the bearers of all qualities, the terms of all relations, and the agents and patients in all interaction.The point to note is that Aristotle begins his investigation into the structure of What Is and the causes by which it is produced by starting from the existence of individual things belonging to the physical order and perceived by the senses. About any such thing we may ask two questions, (1) into what constituent factors can it be logically analysed? (2) and how has it come to exhibit the character which our analysis shows it to have? The answer to these questions will appear from a consideration of two standing antitheses which run through Aristotle's philosophy, the contrast between Matter and Form, and that between Potential and Actual, followed by a recapitulation of his doctrine of the Four Causes, or four senses of the word Cause.Matter and Form.--Consider any completely developed individual thing, whether it is the product of human manufacture, as a copper bowl, or of natural reproduction, as an oak-tree or a horse. We shall see at once that the bowl is like other articles made of the same metal, candlesticks, coal-vases, in being made of the same stuff, and unlike them in having the special shape or structure which renders it fit for being used as a bowl and not for holding a candle or containing coals. So a botanist or a chemist will tell you that the constituent tissues of an oak or horse, or the chemical elements out of which these tissues are built up are of the same kind as those of an ash or an ox, but the oak differs from the ash or the horse from the ox in characteristic structure. We see thus that in any individual thing we can distinguish two components, the stuff of which it consists--which may be identical in kind with the stuff of which things of a very different kind consist--and the structural law of formation or arrangement which is peculiar to the "special" kind of thing under consideration. In the actual individual thing these two are inseparably united; they do not exist side by side, as chemists say the atoms of hydrogen and oxygen do in a drop of water; the law of organisation or structure is manifested in and through the copper, or the various tissues of the living body. Aristotle expresses this by saying that you can distinguish two aspects in an individual, its Matter, (hyle, materia) and its Form (eidos, forma). The individual is the matter as organised in accord with a determinate principle of structure, the form. Of these terms, the former,hyle(materia, matter) means literally timber, and more specifically ship's timbers, and his selection of it to mean what is most exactly rendered by our own word "stuff" may perhaps be due to a reminiscence of an old Pythagorean fancy which looked on the universe as a ship. The word for form is the same as Plato's, and its philosophical uses are closely connected with its mathematical sense, "regular figure," also a Pythagorean technicality which still survives in certain stereotyped phrases in Euclid. Aristotle extends the analysis into Matter and Form by analogy beyond the range of individual substances to everything in which we can distinguish a relatively indeterminate "somewhat" and a law or type of order and arrangement giving it determination. Thus if you consider the relatively fixed or "formed" character of a man in adult life, we may look upon this character as produced out of the "raw material" of tendencies and dispositions, which have received a specific development along definite lines, according to the kind of training to which the mind has been subjected in the "formative" period of its growth. We may therefore speak of native disposition as the matter or stuff of which character is made, and the practical problem of education is to devise a system of training which shall impress on this matter precisely the form required if the grown man is to be a good citizen of a good state. Since a man's character itself is not a substance but a complex of habits or fixed ways of reacting upon suggestions coming from the world around him, this is a good instance of the extension of the antithesis of Matter and Form beyond the category of substance. We see then that Matter in the Aristotelian sense must not be confounded with body; the relatively undetermined factor which receives completer determination by the structural law or Form is Matter, whether it is corporeal or not. This comes out with particular clearness in the metaphysical interpretation put on the logical process of definition by genus and difference. When I define any real kind by specifying a higher and wider class of which it is a sub-kind, and adding the peculiar characteristics which distinguish the sub-kind under consideration from the other sub-kinds of the same genus, the genus may be said to stand to the "differences" as Matter, the relatively indeterminate, to the Form which gives it its structure.We further observe that Matter and Form are strictly correlative. The matter is called so relatively to the form which gives it further determination. When the words are used in their strictest sense, with reference to an individual thing, the Form is taken to mean thelastdetermination by which the thing acquires its complete character, and the Matter is that which has yet to receive this last determination. Thus in the case of a copper globe, the spherical figure is said to be its Form, the copper its material. In the case of the human body, the Matter is the various tissues, muscles, bones, skin, &c. But each of these things which are counted as belonging to the Matter of the globe or the human body has, according to Aristotle, a development behind it. Copper is not an "element" but a specific combination of "elements," and the same thing is even more true of the highly elaborate tissues of the living body. Thus what is Matter relatively to the globe or living body is Matter already determined by Form if we consider it relatively to its own constituents. The so-called "elements" of Empedocles, earth, water, air, fire, are the matter of all chemical compounds, the Form of each compound being its specific law of composition; the immediate or "proximate" Matter of the tissues of the animal body is, according to Aristotle's biology, the "superfluous" blood of the female parent, out of which the various tissues in the offspring are developed, and the Matter of this blood is in turn the various substances which are taken into the body of the parent as food and converted by assimilation into blood. Their Matter, once more, is the earth, air, fire, and water of which they are composed. Thus at every stage of a process of manufacture or growth a fresh Form is superinduced on, or developed within, a Matter which is already itself a combination of Matter and Form relatively to the process by which it has itself been originated. Fully thought out, such a view would lead to the conclusion that in the end the simple ultimate matter of all individual things is one and the same throughout the universe, and has absolutely no definite structure at all. The introduction of Form or determinate structure of any kind would then have to be thought of as coming from an outside source, since structureless Matter cannot be supposed to give itself all sorts of specific determinations, as has been demonstrated in our own times by the collapse of the "Synthetic Philosophy." Aristotle avoids the difficulty by holding that "pure Matter" is a creation of our thought. In actual fact the crudest form in which matter is found is that of the "elements." Since the transmutability of the "elements" is an indispensable tenet in Aristotle's Physics, we cannot avoid regarding earth, water, fire air as themselves determinations by specific Form of a still simpler Matter, though this "prime Matter" "all alone, before a rag of Form is on," is never to be found existing in its simplicity.[#][#]Hudibras, Pt. 1, Canto 1, 560."He had First Matter seen undressed;He took her naked all alone,Before one rag of Form was on."The Potential and the Actual.--So far we have been looking at the analysis of the individual thing, as the current jargon puts it, statically; we have arrived at the antithesis of Matter and Form by contrasting an unfinished condition of anything with its finished condition. But we may study the same contrast dynamically, with special reference to the process of making or growth by which the relatively undetermined or unfinished becomes determined or finished. The contrast of Matter with Form then passes into the contrast between Potentiality and Actuality. What this antithesis means we can best see from the case of the growth of a living organism. Consider the embryos of two animals, or the seeds of two plants. Even a botanist or a physiologist may be unable to pronounce with certainty on the species to which the germ submitted to him belongs, and chemical analysis may be equally at a loss. Even at a later stage of development, the embryo of one vertebrate animal may be indistinguishable from that of another. Yet it is certain that one of two originally indistinguishable germs will grow into an oak and the other into an elm, or one into a chimpanzee and the other into a man. However indistinguishable, they therefore may be said to have different latent tendencies or possibilities of development within them. Hence we may say of a given germ, "though this is not yet actually an oak, it is potentially an oak," meaning not merely that, if uninterfered with, it will in time be an oak, but also that by no interference can it be made to grow into an elm or a beech. So we may look upon all processes of production or development as processes by which what at first possessed only the tendency to grow along certain lines or to be worked up into a certain form, has become actually endowed with the character to which it possessed the tendency. The acorn becomes in process of time an actual oak, the baby an actual man, the copper is made into an actual vase, right education brings out into active exercise the special capacities of the learner. Hence the distinction between Matter and Form may also be expressed by saying that the Matter is the persistent underlyingsubstratumin which the development of the Form takes place, or that the individual when finally determined by the Form is the Actuality of which the undeveloped Matter was the Potentiality. The process of conception, birth, and growth to maturity in Nature, or of the production of a finished article by the "arts" whose business it is to "imitate" Nature, may be said to be one of continuous advance towards the actual embodiment of a Form, or law of organisation, in a Matter having the latent potentiality of developing along those special lines. When Aristotle is speaking most strictly he distinguishes the process by which a Form is realised, which he calls Energeia, from the manifestation of the realised Form, calling the latter Entelechy (literally "finished" or "completed" condition). Often, however, he uses the word Energeia more loosely for the actual manifestation of the Form itself, and in this he is followed by the scholastic writers, who render Energeia byactusoractus purus.One presupposition of this process must be specially noted. It is not an unending process of development of unrealised capacities, but always has an End in the perfectly simple sense of a last stage. We see this best in the case of growth. The acorn grows into the sapling and the sapling into the oak, but there is nothing related to the oak as the oak is to the sapling. The oak does not grow into something else. The process of development from potential to actual in this special case comes to an end with the emergence of the mature oak. In the organic world the end or last state is recognised by the fact that the organism can now exercise the power of reproducing its like. This tendency of organic process to culminate in a last stage of complete maturity is the key to the treatment of the problem of the "true end" of life in Aristotle'sEthics.The Four Causes.--The conception of the world involved in these antitheses of Form and Matter, Potential and Actual, finds its fullest expression in Aristotle's doctrine of the Four Causes or conditions of the production of things. This doctrine is looked on by Aristotle as the final solution of the problem which had always been the central one for Greek philosophy, What are the causes of the world-order? All the previous philosophies he regards as inadequate attempts to formulate the answer to this question which is only given completely by his own system. Hence the doctrine requires to be stated with some fullness. We may best approach it by starting from the literal meaning of the Greek termsaitia,aition, which Aristotle uses to convey the notion of cause.Aitionis properly an adjective used substantially, and means "that on which the legal responsibility for a given state of affairs can be laid." Similarlyaitia, the substantive, means the "credit" for good or bad, the legal "responsibility," for an act. Now when we ask, "what is responsible for the fact that such and such a state of things now exists?" there are four partial answers which may be given, and each of these corresponds to one of the "causes." A complete answer requires the enumeration of them all. We may mention (1) thematterormaterialcause of the thing, (2) the law according to which it has grown or developed, theformorformalcause, (3) the agent with whose initial impulse the development began--the "starting-point of the process," or, as the later Aristotelians call it, theefficientcause, (4) the completed result of the whole process, which is present in the case of human manufacture as a preconceived idea determining the maker's whole method of handling his material, and in organic development in Nature as implied in and determining the successive stages of growth--theendorfinalcause. If any one of these had been different, the resultant state of things would also have been different. Hence all four must be specified in completely accounting for it. Obvious illustrations can be given from artificial products of human skill, but it seems clear that it was rather reflection on the biological process of reproduction and growth which originally suggested the analysis. Suppose we ask what was requisite in order that there should be now an oak on a given spot. There must have been (1) a germ from which the oak has grown, and this germ must have had the latent tendencies towards development which are characteristic of oaks. This is the material cause of the oak. (2) This germ must have followed a definite law of growth; it must have had a tendency to grow in the way characteristic of oaks and to develop the structure of an oak, not that of a plane or an ash. This is form or formal cause. (3) Also the germ of the oak did not come from nowhere; it grew on a parent oak. The parent oak and its acorn-bearing activity thus constitute theefficientcause of the present oak. (4) And there must be a final stage to which the whole process of growth is relative, in which the germ or sapling is no longer becoming but is an adult oak bearing fresh acorns. This is theendof the process. One would not be going far wrong in saying that Aristotle's biological cast of thought leads him to conceive of this "end" in the case of reproduction as a sub-conscious purpose, just as the workman's thought of the result to be attained by his action forms a conscious directing purpose in the case of manufacture. Both in Nature and in "art" the "form," the "efficient cause," and the "end" tend to coalesce. Thus in Nature "a man begets a man," organic beings give birth to other organic beings of the same kind, or, in the technical language of the Aristotelian theory of Causation, the efficient cause produces, as the "end" of its action, a second being having the same "form" as itself, though realised in different "matter," and numerically distinct from itself. Thus the efficient cause (i.e.the parent) is a "form" realised in matter, and the "end" is the same "form" realised in other matter. So in "products of art" the true "source of the process" is the "form" the realisation of which is the "end" or final cause, only with this difference, that as efficient cause the "form" exists not in the material but by way of "idea" or "representation" in the mind of the craftsman. A house does not produce another house, but the house as existing in "idea" in the builder's mind sets him at work building, and so produces a corresponding house in brick or stone. Thus the ultimate opposition is between the "cause as matter," a passive and inert substratum of change and development and the "formal" cause which, in the sense just explained, is one with both the "efficient" or starting-point, and the "end" or goal of development. It will, of course, be seen that individual bearers of "forms" are indispensable in the theory; hence the notion ofactivityis essential to the causal relation. It is a relation between things, not between events. Aristotle has no sense of the word cause corresponding to Mill's conception of a cause as an event which is the uniform precursor of another event.Two more remarks may be made in this connection. (1) The prominence of the notion of "end" gives Aristotle's philosophy a thorough-going "ideological" character. God and Nature, he tells us, do nothing aimlessly. We should probably be mistaken if we took this to mean that "God and Nature" act everywhere with conscious design. The meaning is rather that every natural process has a last stage in which the "form" which was to begin with present in the agent or "source of change" is fully realised in the matter in which the agent has set up the process of change. The normal thing ise.g.for animals to reproduce "their kind"; if the reproduction is imperfect or distorted, as in monstrous births, this is an exception due to the occasional presence in "matter" of imperfections which hinder the course of development, and must be regarded as "contrary to the normal course of Nature." So hybrid reproduction is exceptional and "against Nature," and this is shown by the sterility of hybrids, a sort of lesser monstrosity. Even females, being "arrested developments," are a sort of still minor deviation from principle. (2) It may just be mentioned that Aristotle has a classification of efficient causes under the three heads of Nature, Intelligence (or Man), and Chance. The difference between Nature and Man or Intelligence as efficient causes has already been illustrated. It is that in causation by Nature, such as sexual reproduction, or the assimilation of nutriment, or the conversion of one element into another in which Aristotle believed, the form which is superinduced on the matter by the agent already exists in the agent itself asitsform. The oak springs from a parent oak, the conversion of nutriment into organic tissue is due to the agency of already existing organic tissue. In the case of human intelligence or art, the "form" to be superinduced exists in the agent not ashischaracteristic form, but by way of representation, as a contemplated design. The man who builds a house is not himself a house; the form characteristic of a house is very different from that characteristic of a man, but it is present in contemplation to the builder before it is embodied in the actual house. A word may be added about the third sort of efficient causality, causation by chance. This is confined to cases which are exceptions from the general course of Nature, remarkable coincidences. It is what we may call "simulated purposiveness." When something in human affairs happens in a way which subserves the achievement of a result but was not really brought about by any intention to secure the result, we speak of it as a remarkable coincidence. Thus it would be a coincidence if a man should be held to ransom by brigands and his best friend should, without knowing anything of the matter, turn up on the spot with the means of ransoming him. The events could not have happened more opportunely if they had been planned, and yet they were not planned but merely fell out so: and since such a combination of circumstances simulating design is unusual, it is not proper to say that the events happened "in the course of Nature." We therefore say it happened by chance. This doctrine of chance has its significance for mediæval Ethics. In an age when the Protestant superstition that worldly success is proof of nearness to God had not yet been invented, the want of correspondence between men's "deserts" and their prosperity was accounted for by the view that the distribution of worldly goods is, as a rule, the work of Fortune or Chance in the Aristotelian sense; that is, it is due to special coincidences which may look like deliberate design but are not really so. (See the elaborate exposition of this in Dante,Inferno, vii. 67-97.)Motion.--We have seen that causation, natural or artificial, requires the production in a certain "matter" of a certain "form" under the influence of a certain "agent." What is the character of the process set up by the agent in the matter and culminating in the appearance of the form? Aristotle answers that it is Motion (kinesis). The effect of the agent on the matter is to set up in it a motion which ends in its assuming a definite form. The important point to be noted here is that Aristotle regards this motion as falling wholly within the matter which is to assume the form. It is not necessary that the agent should itself be in motion, but only that it should induce motion in something else. Thus in all cases of intentional action the ultimate efficient cause is the "idea of the result to be attained," but this idea does not move about. By its presence to the mind it sets something else (the members of the body) moving. This conception of an efficient cause which, not moving itself, by its mere presence induces movement in that to which it is present, is of the highest importance in Aristotle's theology. Of course it follows that since the motion by which the transition from potentiality to actuality is achieved falls wholly within the matter acted upon, Aristotle is not troubled with any of the questions as to the way in which motion can be transferred from one body to another which were so much agitated in the early days of the modern mechanical interpretation of natural processes. Aristotle's way of conceiving Nature is thoroughly non-mechanical, and approximates to what would now be called the ascription of vital or quasi-vital characteristics to the inorganic. As, in the causality of "art" the mere presence of the "form" to be embodied in a given material to the mind of the craftsman brings about and directs the process of manufacture, so in some analogous fashion the presence of an efficient cause in Nature to that on which it works is thought of as itself constituting the "efficiency" of the cause. As Lotze phrases it, things "take note of" one another's compresence in the universe, or we might say the efficient cause and that on which it exercises its efficiency areen rapport. "Matter" is sensitive to the presence of the "efficient cause," and in response to this sensitivity, puts forth successive determinations, expands its latent tendencies on definite lines.The name "motion" has a wider sense for Aristotle than it has for ourselves. He includes under the one common name all the processes by which things come to be what they are or cease to be what they have been. Thus he distinguishes the following varieties of "motion":generation(the coming of an individual thing into being), with its oppositedecayorcorruption(the passing of a thing out of being),alteration(change ofqualityin a thing),augmentationanddiminution(change in themagnitudeof a thing),motion through space(of which latter he recognises two sub-species, rectilineartransferenceandrotationin a circular orbit about an axis). It is this last variety, motion through space, which is the most fundamental of all, since its occurrence is involved in that of any of the other types of process mentioned, though Aristotle does not hold the thorough-going mechanical view that the other processes are only apparent, and that, as we should put it, qualitative change is a mere disguise which mechanical motion wears for our senses.The Eternity of Motion.--Certain very important consequences follow from the conception of efficient causation which we have been describing. Aristotle has no sympathy with the "evolutionist" views which had been favoured by some of his predecessors. According to his theory of organic generation, "it takes a man to beget a man "; where there is a baby, there must have been a father. Biological kinds representing real clefts in Nature, the process of the production of a young generation by an already adult generation must be thought of as without beginning and without end. There can be no natural "evolution" of animals of one species from individuals of a different kind. Nor does it occur to Aristotle to take into account the possibility of "Creationism," the sudden coming into being of a fully fledged first generation at a stroke. This possibility is excluded by the doctrine that the "matter" of a thing must exist beforehand as an indispensable condition of the production of that thing. Every baby, as we said, must have had a father, but that father must also have been a baby before he was a full-grown man. Hence the perpetuation of unchanging species must be without beginning and without end. And it is implied that all the various processes, within and without the organism, apart from which its life could not be kept up, must be equally without beginning and without end. The "cosmos," or orderly world of natural processes, is strictly "eternal"; "motion" is everlasting and continuous, or unbroken. Even the great Christian theologians who built upon Aristotle could not absolutely break with him on this point. St. Thomas, though obliged to admit that the world was actually created a few thousand years before his own time, maintains that this can only be known to be true from revelation, philosophically it is equably tenable that the world should have been "created from all eternity." And it is the general doctrine of scholasticism that the expression "creation" only denotes the absolute dependence of the world on God for its being. When we say "God created the world out of nothing," we mean that He did not make it out of pre-existing matter, that it depends for its being on Him only; the expression is purely negative in its import.God.--With the doctrine of the eternity of the world and the processes which make up its life we come close to the culminating theory of Aristotelian First Philosophy, its doctrine of God, as the eternal, unchanging source of all change, movement, and process. All motion is a process within matter by which the forms latent in it are brought into actual manifestation. And the process only takes place in the presence of an adequate efficient cause or source of motion. Hence the eternity of natural processes involves the existence of one or more eternal sources of motion. For, if we do not admit the existence of an unoriginated and ever-present source or sources of motion, our only alternative is to hold that the world-process is due to a series of sources of motion existing successively. But such a view would leave the unity and unbroken continuity of the world-process unaccounted for. It would give us a succession of processes, temporally contiguous, not one unbroken process. Hence we argue from the continuity of motion to its dependence on a source or sources which are permanent and present throughout the whole everlasting world-process. And when we come to the question whether there is only one such ultimate source of movement for the whole universe, or several, Aristotle's answer is that the supreme "Unmoved Mover" is one. One is enough for the purpose, and the law of parcimony forbids us to assume the superfluous. This then is the Aristotelian conception of God and God's relation to the world. God is the one supreme unchanging being to whose presence the world responds with the whole process of cosmic development, the ultimate educer of the series of "forms" latent in the "matter" of the world into actual manifestation. Standing, as He does, outside the whole process which by His mere presence He initiates in Nature, He is not himself a composite of "form" and "matter," as the products of development are. He is a pure individual "form" or "actuality," with no history of gradual development behind it. Thus He is a purely immaterial being, indispensable to the world's existence but transcending it and standing outside it.HowHis presence inspires the world to move Aristotle tries to explain by the metaphor of appetition. Just as the good I desire and conceive, without itself "moving" "moves" my appetition, so God moves the universe by being its good. This directly brings about a uniform unbroken rotation of the whole universe round its axis (in fact, the alternation of day and night). And since this rotation is communicated from the outermost "sphere" of heaven to all the lesser "spheres" between it and the immovable centre, the effects of God's presence are felt universally. At the same time, we must note that though God is the supreme Mover of the Universe, He is not regarded by Aristotle as its Creator, even in the sense in which creation can be reconciled with the eternity of the world. For the effect of God's presence is simply to lead to the development of "form" in an already existing "matter." Without God there could be no "form" or order in things, not even as much as is implied in the differentiation of matter into the four "elements," yet "primary matter" is no less than God a precondition of all that happens.It is characteristic of Aristotle that his God is as far from discharging the functions of a Providence as He is from being a Creator. His "activity" is not, as Plato had made it, that of the great "Shepherd of the sheep." As far as the world is concerned, God's only function is to be there to move its appetition. For the rest, the unbroken activity of this life is directed wholly inward. Aristotle expressly calls it an "activity of immobility." More precisely, he tells us, it is activity of thought, exercised unbrokenly and everlastingly upon the only object adequate to exercise God's contemplation, Himself. His life is one of everlastingself-contemplation or "thinking of thought itself." Like all unimpeded exercise of activity, it is attended by pleasure, and as the activity is continuous, so the pleasure of it is continuous too. At our best, when we give ourselves up to the pure contemplative activity of scientific thought or æsthetic appreciation, we enter for a while into this divine life and share the happiness of God. But that is a theme for our chapter on theEthics.It is a far cry from this conception of a God untroubled by care for a world to which He is only related as the object of its aspiration to the God who cares even for the fall of the sparrow and of whom it is written,Sic Deus dilexit mundum, but it was the standing task of the philosophical theologians of the Middle Ages to fuse the two conceptions. Plato's God, who, if not quite the Creator, is the "Father and Fashioner" of us all, and keeps providential watch over the world He has fashioned, would have lent Himself better to their purposes, but Plato was held by the mediæval church to have denied the resurrection of the body. The combination of Aristotle's Theism with the Theism of early Christianity was effected by exquisitely subtle logical devices, but even in St. Thomas one cannot help seeing the seams.Nor can one help seeing in Aristotle's own doctrine the usual want of coherence between an initial anti-Platonic bias and a final reversion to the very Platonic positions Aristotle is fond of impugning. We are told at the outset that the Platonic "separate forms" are empty names, and that the real individual thing is always a composite of matter and a form which only exists "in matter." We find in the end that the source of the whole process by which "matter" becomes imbued with "form" is a being which is "pure" form and stands outside the whole development which its presence sets up. And the issue of Aristotle's warning against "poetic metaphors" is the doctrine that God moves the world by being "the object of the world's desire."
[#] This simple expression acquires a mysterious appearance in mediæval philosophy from the standing mistranslationnotiora naturæ, "better known to nature."
It follows that Aristotle, after all, admits the disparateness of sense-perception and scientific knowledge. Sense-perception of itself never gives us scientific truth, because it can only assure us that a fact is so; it cannotexplainthe fact by showing its connection with the rest of the system of facts, "it does not give thereasonfor the fact." Knowledge of perception is always "immediate," and for that very reason is never scientific. If we stood on the moon and saw the earth, interposing between us and the sun, we should still not have scientific knowledge about the eclipse, because "we should still have to ask for thereason why." (In fact, we should not know the reasonwhywithout a theory of light including the proposition that light-waves are propagated in straight lines and several others.) Similarly Aristotle insists that Induction does not yield scientific truth. "He who makes an induction points out something, but does not demonstrate anything."
For instance, if we know thateachspecies of animal which is without a gall is long-lived, we may make the induction thatallanimals without a gall are long-lived, but in doing so we have got no nearer to seeingwhyorhowthe absence of a gall makes for longevity. The question which we may raise in science may all be reduced to four heads, (1) Does this thing exist? (2) Does this event occur? (3) If the thing exists, precisely what is it? and (4) If the event occurs,whydoes it occur? and science has not completed its task unless it can advance from the solution of the first two questions to that of the latter two. Science is no mere catalogue of things and events, it consists of inquiries into the "real essences" and characteristics of things and the laws of connection between events.
Looking at scientific reasoning, then, from the point of view of its formal character, we may say that all science consists in the search for "middle terms" of syllogisms, by which to connect the truth which appears as a conclusion with the less complex truths which appear as the premisses from which it is drawn. When we ask, "does such a thing exist?" or "does such an event happen?" we are asking, "is there a middle term which can connect the thing or event in question with the rest of known reality?" Since it is a rule of the syllogism that the middle term must be taken universally, at least once in the premisses, the search for middle terms may also be described as the search for universals, and we may speak of science as knowledge of the universal interconnections between facts and events.
A science, then, may be analysed into three constituents. These are: (1) a determinate class of objects which form the subject-matter of its inquiries. In an orderly exhibition of the contents of the science, these appear, as in Euclid, as the initial data about which the science reasons; (2) a number of principles, postulates, and axioms, from which our demonstrations must start. Some of these will be principles employed in all scientific reasoning. Others will be specific to the subject-matter with which a particular science is concerned; (3) certain characteristics of the objects under study which can be shown by means of our axioms and postulates to follow from our initial definitions, theaccidentia per seof the objects defined. It is these last which are expressed by the conclusions of scientific demonstration. We are said to know scientifically that B is true of A when we show that this follows, in virtue of the principles of some science, from the initial definition of A. Thus if we convinced ourselves that the sum of the angles of a plane triangle is equal to two right angles by measurement, we could not be said to have scientific knowledge of the proposition. But if we show that the same proposition follows from the definition of a plane triangle by repeated applications of admitted axioms or postulates of geometry, our knowledge is genuinely scientific. We now know that it is so, and we seewhyit is so; we see the connection of this truth with the simple initial truths of geometry.
This leads us to the consideration of the most characteristic point of Aristotle's whole theory. Science is demonstrated knowledge, that is, it is the knowledge that certain truths follow from still simpler truths. Hence the simplest of all the truths of any science cannot themselves be capable of being known by inference. You cannot infer that the axioms of geometry are true because its conclusions are true, since the truth of the conclusions is itself a consequence of the truth of the axioms. Nor yet must you ask for demonstration of the axioms as consequences of still simpler premisses, because if all truths can be proved, they ought to be proved, and you would therefore require an infinity of successive demonstrations to prove anything whatever. But under such conditions all knowledge of demonstrated truth would be impossible. The first principles of any science must therefore be indemonstrable. They must be known, as facts of sense-perception are known, immediately and not mediately. How then do we come by our knowledge of them? Aristotle's answer to this question appears at first sight curiously contradictory. He seems to say that these simplest truths are apprehended intuitively, or on inspection, as self-evident by Intelligence or Mind. On the other hand, he also says that they are knownto usas a result of induction from sense-experience. Thus heseemsto be either a Platonist or an empiricist, according as you choose to remember one set of his utterances or another, and this apparent inconsistency has led to his authority being claimed in their favour by thinkers of the most widely different types. But more careful study will show that the seeming confusion is due to the fact that he tries to combine in one statement his answers to two quite different questions, (1) how we come to reflect on the axioms, (2) what evidence there is for their truth. To the first question he replies, "by induction from experience," and so far he might seem to be a precursor of John Stuart Mill. Successive repetitions of the same sense-perceptions give rise to a single experience, and it is by reflection on experience that we become aware of the most ultimate simple and universal principles. We might illustrate his point by considering how the thought that two and two are four may be brought before a child's mind. We might first take two apples, and two other apples and set the child to count them. By repeating the process with different apples we may teach the child to dissociate the result of the counting from the particular apples employed, and to advance to the thought, "any two apples and any two other apples make four apples." Then we might substitute pears or cherries for the apples, so as to suggest the thought, "two fruits and two fruits make four fruits." And by similar methods we should in the end evoke the thought, "any two objects whatever and any other two objects whatever make four objects." This exactly illustrates Aristotle's conception of the function of induction, or comparison of instances, in fixing attention on a universal principle of which one had not been conscious before the comparison was made.
Now comes in the point where Aristotle differs wholly from all empiricists, later and earlier. Mill regards the instances produced in the induction as having a double function; they not merely fix the attention on the principle, they also are the evidence of its truth. This gives rise to the greatest difficulty in his whole logical theory. Induction by imperfect enumeration is pronounced to be (as it clearly is) fallacious, yet the principle of the uniformity of Nature which Mill regards as the ultimate premiss of all science, is itself supposed to be proved by this radically fallacious method. Aristotle avoids a similar inconsistency by holding that the sole function of the induction is to fix our attention on a principle which it does not prove. He holds that ultimate principles neither permit of nor require proof. When the induction has done its work in calling attention to the principle, you have to see for yourself that the principle is true. You see that it is true by immediate inspection just as in sense-perception you have to see that the colour before your eyes is red or blue. This is why Aristotle holds that the knowledge of the principles of science is not itself science (demonstrated knowledge), but what he calls intelligence, and we may call intellectual intuition. Thus his doctrine is sharply distinguished not only from empiricism (the doctrine that universal principles are proved by particular facts), but also from all theories of the Hegelian type which regard the principles and the facts as somehow reciprocally proving each other, and from the doctrine of some eminent modern logicians who hold that "self-evidence" is not required in the ultimate principles of science, as we are only concerned in logic with the question what consequences follow from our initial assumptions, and not with the truth or falsehood of the assumptions themselves.
The result is that Aristotle does little more than repeat the Platonic view of the nature of science. Science consists of deductions from universal principles which sensible experience "suggests," but into which, as they are apprehended by a purely intellectual inspection, no sense-data enter as constituents. The apparent rejection of "transcendental moonshine" has, after all, led to nothing. The only difference between Plato and his scholar lies in the clearness of intellectual vision which Plato shows when he expressly maintains in plain words that the universals of exact science are not "in" our sense-perceptions and therefore to be extracted from them by a process of abstraction, but are "apart from" or "over" them, and form an ideal system of interconnected concepts which the experiences of sense merely "imitate" or make approximation to.
One more point remains to be considered to complete our outline of the Aristotelian theory of knowledge. The sciences have "principles" which are discerned to be true by immediate inspection. But what if one man professes to see the self-evident truth of such an alleged principle, while another is doubtful of its truth, or even denies it? There can be no question of silencing the objector by a demonstration, since no genuine simple principle admits of demonstration. All that can be done,e.g.if a man doubts whether things equal to the same thing are equal to one another, or whether the law of contradiction is true, is to examine the consequences of a denial of the axiom and to show that they include some which are false, or which your antagonist at least considers false. In this way, by showing the falsity of consequences which follow from the denial of a given "principle," you indirectly establish its truth. Now reasoning of this kind differs from "science" precisely in the point that you take as your major premiss, not what you regard as true, but the opposite thesis of your antagonist, which you regard as false. Your object is not to prove a true conclusion but to show your opponent thathispremisses lead to false conclusions. This is "dialectical" reasoning in Aristotle's sense of the word,i.e.reasoning not from your own but from some one else's premisses. Hence the chief philosophical importance which Aristotle ascribes to "dialectic" is that it provides a method of defending the undemonstrable axioms against objections. Dialectic of this kind became highly important in the mediæval Aristotelianism of the schoolmen, with whom it became a regular method, as may be seene.g.in theSummaof St. Thomas, to begin their consideration of a doctrine by a preliminary rehearsal of all the arguments they could find or devise against the conclusion they meant to adopt. Thus the first division of any article in theSumma Theologiæof Thomas is regularly constituted by arguments based on the premisses of actual or possible antagonists, and is strictly dialectical. (To be quite accurate Aristotle should, of course, have observed that this dialectical method of defending a principle becomes useless in the case of a logical axiom which is presupposed by all deduction. For this reason Aristotle falls into fallacy when he tries to defend the law of contradiction by dialectic. It is true that if the law be denied, then any and every predicate may be indifferently ascribed to any subject. But until the law of contradiction has been admitted, you have no right to regard it as absurd to ascribe all predicates indiscriminately to all subjects. Thus, it is only assumed laws which arenotultimate laws of logic that admit of dialectical justification. If a truth is so ultimate that it has either to be recognised by direct inspection or not at all, there can be no arguing at all with one who cannot or will not see it.)
CHAPTER III
FIRST PHILOSOPHY
First Philosophy is defined by Aristotle as a "science which considers What Is simply in its character of Being, and the properties which it has as such." That there is, or ought to be, such a science is urged on the ground that every "special" science deals only with some restricted department of what is, and thus considers its subject-matter not universally in its character of being, or being real, but as determined by some more special condition. Thus, First Philosophy, the science which attempts to discover the most ultimate reasons of, or grounds for, the character of things in general cannot be identified with any of the "departmental" sciences. The same consideration explains why it is "First Philosophy" which has to disentangle the "principles" of the various sciences, and defend them by dialectic against those who impugn them. It is no part of the duty of a geometer or a physicist to deal with objections to such universal principles of reasoning as the law of contradiction. They may safely assume such principles; if they are attacked, it is not by specifically geometrical or physical considerations that they can be defended. Even the "principles of the special sciences" have not to be examined and defended by the special sciences. They are the starting-points of the sciences which employ them; these sciences are therefore justified in requiring that they shall be admitted as a condition of geometrical, or physical, or biological demonstrations. If they are called in question, the defence of them is the business of logic.
First Philosophy, then, is the study of "What Is simply as such," the universal principles of structure without which there could be no ordered system of knowable objects. But the word "is" has more than one sense. There are as many modes of being as there are types of predication. "Substances," men, horses, and the like, have their own specific mode of being--they are things; qualities, such as green or sweet, have a different mode of being--they are not things, but "affections" or "attributes" of things. Actions, again, such as building, killing, are neither things nor yet "affections" of things; their mode of being is that they are processes which produce or destroy things. First Philosophy is concerned with the general character of all these modes of being, but it is specially concerned with that mode of being which belongs tosubstances. For this is the most primary of all modes of being. We had to introduce a reference to it in our attempt to say what the mode of being of qualities and actions is, and it would have been the same had our illustrations been drawn from any other "categories." Hence the central and special problem of First Philosophy is to analyse the notion of substance and to show the causes of the existence of substances.
Next, we have to note that the word "substance" itself has two senses. When we spoke of substance as one of the categories we were using it in a secondary sense. We meant by substances "horse," "man," and the rest of the "real kinds" which we find in Nature, and try to reproduce in a scientific classification. In this sense of the word "substances" are a special class ofpredicates, as when we affirm of Plato that he is a man, or of Bucephalus that he is a horse. But in the primary sense a substance means an absolutely individual thing, "thisman," or "thishorse." We may therefore define primary substances from the logician's point of view by saying that they can be only subjects of predication, never predicates. Or again, it is peculiar to substances, that while remaining numerically one a substance admits of incompatible determinations, as Socrates, remaining one and the same Socrates, is successively young and old. This is not true of "qualities," "actions," and the rest. The same colour cannot be first white and then black; the same act cannot be first bad and then good. Thus we may say that individual substances are the fixed and permanent factors in the world of mutability, the invariants of existence. Processes go on in them, they run the gamut of changes from birth to decay, processes take placeamongthem, they act on and are acted on by one another, they fluctuate in their qualities and their magnitude, but so long as a substance exists it remains numerically one and the same throughout all these changes. Their existence is the first and most fundamental condition of the existence of the universe, since they are the bearers of all qualities, the terms of all relations, and the agents and patients in all interaction.
The point to note is that Aristotle begins his investigation into the structure of What Is and the causes by which it is produced by starting from the existence of individual things belonging to the physical order and perceived by the senses. About any such thing we may ask two questions, (1) into what constituent factors can it be logically analysed? (2) and how has it come to exhibit the character which our analysis shows it to have? The answer to these questions will appear from a consideration of two standing antitheses which run through Aristotle's philosophy, the contrast between Matter and Form, and that between Potential and Actual, followed by a recapitulation of his doctrine of the Four Causes, or four senses of the word Cause.
Matter and Form.--Consider any completely developed individual thing, whether it is the product of human manufacture, as a copper bowl, or of natural reproduction, as an oak-tree or a horse. We shall see at once that the bowl is like other articles made of the same metal, candlesticks, coal-vases, in being made of the same stuff, and unlike them in having the special shape or structure which renders it fit for being used as a bowl and not for holding a candle or containing coals. So a botanist or a chemist will tell you that the constituent tissues of an oak or horse, or the chemical elements out of which these tissues are built up are of the same kind as those of an ash or an ox, but the oak differs from the ash or the horse from the ox in characteristic structure. We see thus that in any individual thing we can distinguish two components, the stuff of which it consists--which may be identical in kind with the stuff of which things of a very different kind consist--and the structural law of formation or arrangement which is peculiar to the "special" kind of thing under consideration. In the actual individual thing these two are inseparably united; they do not exist side by side, as chemists say the atoms of hydrogen and oxygen do in a drop of water; the law of organisation or structure is manifested in and through the copper, or the various tissues of the living body. Aristotle expresses this by saying that you can distinguish two aspects in an individual, its Matter, (hyle, materia) and its Form (eidos, forma). The individual is the matter as organised in accord with a determinate principle of structure, the form. Of these terms, the former,hyle(materia, matter) means literally timber, and more specifically ship's timbers, and his selection of it to mean what is most exactly rendered by our own word "stuff" may perhaps be due to a reminiscence of an old Pythagorean fancy which looked on the universe as a ship. The word for form is the same as Plato's, and its philosophical uses are closely connected with its mathematical sense, "regular figure," also a Pythagorean technicality which still survives in certain stereotyped phrases in Euclid. Aristotle extends the analysis into Matter and Form by analogy beyond the range of individual substances to everything in which we can distinguish a relatively indeterminate "somewhat" and a law or type of order and arrangement giving it determination. Thus if you consider the relatively fixed or "formed" character of a man in adult life, we may look upon this character as produced out of the "raw material" of tendencies and dispositions, which have received a specific development along definite lines, according to the kind of training to which the mind has been subjected in the "formative" period of its growth. We may therefore speak of native disposition as the matter or stuff of which character is made, and the practical problem of education is to devise a system of training which shall impress on this matter precisely the form required if the grown man is to be a good citizen of a good state. Since a man's character itself is not a substance but a complex of habits or fixed ways of reacting upon suggestions coming from the world around him, this is a good instance of the extension of the antithesis of Matter and Form beyond the category of substance. We see then that Matter in the Aristotelian sense must not be confounded with body; the relatively undetermined factor which receives completer determination by the structural law or Form is Matter, whether it is corporeal or not. This comes out with particular clearness in the metaphysical interpretation put on the logical process of definition by genus and difference. When I define any real kind by specifying a higher and wider class of which it is a sub-kind, and adding the peculiar characteristics which distinguish the sub-kind under consideration from the other sub-kinds of the same genus, the genus may be said to stand to the "differences" as Matter, the relatively indeterminate, to the Form which gives it its structure.
We further observe that Matter and Form are strictly correlative. The matter is called so relatively to the form which gives it further determination. When the words are used in their strictest sense, with reference to an individual thing, the Form is taken to mean thelastdetermination by which the thing acquires its complete character, and the Matter is that which has yet to receive this last determination. Thus in the case of a copper globe, the spherical figure is said to be its Form, the copper its material. In the case of the human body, the Matter is the various tissues, muscles, bones, skin, &c. But each of these things which are counted as belonging to the Matter of the globe or the human body has, according to Aristotle, a development behind it. Copper is not an "element" but a specific combination of "elements," and the same thing is even more true of the highly elaborate tissues of the living body. Thus what is Matter relatively to the globe or living body is Matter already determined by Form if we consider it relatively to its own constituents. The so-called "elements" of Empedocles, earth, water, air, fire, are the matter of all chemical compounds, the Form of each compound being its specific law of composition; the immediate or "proximate" Matter of the tissues of the animal body is, according to Aristotle's biology, the "superfluous" blood of the female parent, out of which the various tissues in the offspring are developed, and the Matter of this blood is in turn the various substances which are taken into the body of the parent as food and converted by assimilation into blood. Their Matter, once more, is the earth, air, fire, and water of which they are composed. Thus at every stage of a process of manufacture or growth a fresh Form is superinduced on, or developed within, a Matter which is already itself a combination of Matter and Form relatively to the process by which it has itself been originated. Fully thought out, such a view would lead to the conclusion that in the end the simple ultimate matter of all individual things is one and the same throughout the universe, and has absolutely no definite structure at all. The introduction of Form or determinate structure of any kind would then have to be thought of as coming from an outside source, since structureless Matter cannot be supposed to give itself all sorts of specific determinations, as has been demonstrated in our own times by the collapse of the "Synthetic Philosophy." Aristotle avoids the difficulty by holding that "pure Matter" is a creation of our thought. In actual fact the crudest form in which matter is found is that of the "elements." Since the transmutability of the "elements" is an indispensable tenet in Aristotle's Physics, we cannot avoid regarding earth, water, fire air as themselves determinations by specific Form of a still simpler Matter, though this "prime Matter" "all alone, before a rag of Form is on," is never to be found existing in its simplicity.[#]
[#]Hudibras, Pt. 1, Canto 1, 560.
"He had First Matter seen undressed;He took her naked all alone,Before one rag of Form was on."
The Potential and the Actual.--So far we have been looking at the analysis of the individual thing, as the current jargon puts it, statically; we have arrived at the antithesis of Matter and Form by contrasting an unfinished condition of anything with its finished condition. But we may study the same contrast dynamically, with special reference to the process of making or growth by which the relatively undetermined or unfinished becomes determined or finished. The contrast of Matter with Form then passes into the contrast between Potentiality and Actuality. What this antithesis means we can best see from the case of the growth of a living organism. Consider the embryos of two animals, or the seeds of two plants. Even a botanist or a physiologist may be unable to pronounce with certainty on the species to which the germ submitted to him belongs, and chemical analysis may be equally at a loss. Even at a later stage of development, the embryo of one vertebrate animal may be indistinguishable from that of another. Yet it is certain that one of two originally indistinguishable germs will grow into an oak and the other into an elm, or one into a chimpanzee and the other into a man. However indistinguishable, they therefore may be said to have different latent tendencies or possibilities of development within them. Hence we may say of a given germ, "though this is not yet actually an oak, it is potentially an oak," meaning not merely that, if uninterfered with, it will in time be an oak, but also that by no interference can it be made to grow into an elm or a beech. So we may look upon all processes of production or development as processes by which what at first possessed only the tendency to grow along certain lines or to be worked up into a certain form, has become actually endowed with the character to which it possessed the tendency. The acorn becomes in process of time an actual oak, the baby an actual man, the copper is made into an actual vase, right education brings out into active exercise the special capacities of the learner. Hence the distinction between Matter and Form may also be expressed by saying that the Matter is the persistent underlyingsubstratumin which the development of the Form takes place, or that the individual when finally determined by the Form is the Actuality of which the undeveloped Matter was the Potentiality. The process of conception, birth, and growth to maturity in Nature, or of the production of a finished article by the "arts" whose business it is to "imitate" Nature, may be said to be one of continuous advance towards the actual embodiment of a Form, or law of organisation, in a Matter having the latent potentiality of developing along those special lines. When Aristotle is speaking most strictly he distinguishes the process by which a Form is realised, which he calls Energeia, from the manifestation of the realised Form, calling the latter Entelechy (literally "finished" or "completed" condition). Often, however, he uses the word Energeia more loosely for the actual manifestation of the Form itself, and in this he is followed by the scholastic writers, who render Energeia byactusoractus purus.
One presupposition of this process must be specially noted. It is not an unending process of development of unrealised capacities, but always has an End in the perfectly simple sense of a last stage. We see this best in the case of growth. The acorn grows into the sapling and the sapling into the oak, but there is nothing related to the oak as the oak is to the sapling. The oak does not grow into something else. The process of development from potential to actual in this special case comes to an end with the emergence of the mature oak. In the organic world the end or last state is recognised by the fact that the organism can now exercise the power of reproducing its like. This tendency of organic process to culminate in a last stage of complete maturity is the key to the treatment of the problem of the "true end" of life in Aristotle'sEthics.
The Four Causes.--The conception of the world involved in these antitheses of Form and Matter, Potential and Actual, finds its fullest expression in Aristotle's doctrine of the Four Causes or conditions of the production of things. This doctrine is looked on by Aristotle as the final solution of the problem which had always been the central one for Greek philosophy, What are the causes of the world-order? All the previous philosophies he regards as inadequate attempts to formulate the answer to this question which is only given completely by his own system. Hence the doctrine requires to be stated with some fullness. We may best approach it by starting from the literal meaning of the Greek termsaitia,aition, which Aristotle uses to convey the notion of cause.Aitionis properly an adjective used substantially, and means "that on which the legal responsibility for a given state of affairs can be laid." Similarlyaitia, the substantive, means the "credit" for good or bad, the legal "responsibility," for an act. Now when we ask, "what is responsible for the fact that such and such a state of things now exists?" there are four partial answers which may be given, and each of these corresponds to one of the "causes." A complete answer requires the enumeration of them all. We may mention (1) thematterormaterialcause of the thing, (2) the law according to which it has grown or developed, theformorformalcause, (3) the agent with whose initial impulse the development began--the "starting-point of the process," or, as the later Aristotelians call it, theefficientcause, (4) the completed result of the whole process, which is present in the case of human manufacture as a preconceived idea determining the maker's whole method of handling his material, and in organic development in Nature as implied in and determining the successive stages of growth--theendorfinalcause. If any one of these had been different, the resultant state of things would also have been different. Hence all four must be specified in completely accounting for it. Obvious illustrations can be given from artificial products of human skill, but it seems clear that it was rather reflection on the biological process of reproduction and growth which originally suggested the analysis. Suppose we ask what was requisite in order that there should be now an oak on a given spot. There must have been (1) a germ from which the oak has grown, and this germ must have had the latent tendencies towards development which are characteristic of oaks. This is the material cause of the oak. (2) This germ must have followed a definite law of growth; it must have had a tendency to grow in the way characteristic of oaks and to develop the structure of an oak, not that of a plane or an ash. This is form or formal cause. (3) Also the germ of the oak did not come from nowhere; it grew on a parent oak. The parent oak and its acorn-bearing activity thus constitute theefficientcause of the present oak. (4) And there must be a final stage to which the whole process of growth is relative, in which the germ or sapling is no longer becoming but is an adult oak bearing fresh acorns. This is theendof the process. One would not be going far wrong in saying that Aristotle's biological cast of thought leads him to conceive of this "end" in the case of reproduction as a sub-conscious purpose, just as the workman's thought of the result to be attained by his action forms a conscious directing purpose in the case of manufacture. Both in Nature and in "art" the "form," the "efficient cause," and the "end" tend to coalesce. Thus in Nature "a man begets a man," organic beings give birth to other organic beings of the same kind, or, in the technical language of the Aristotelian theory of Causation, the efficient cause produces, as the "end" of its action, a second being having the same "form" as itself, though realised in different "matter," and numerically distinct from itself. Thus the efficient cause (i.e.the parent) is a "form" realised in matter, and the "end" is the same "form" realised in other matter. So in "products of art" the true "source of the process" is the "form" the realisation of which is the "end" or final cause, only with this difference, that as efficient cause the "form" exists not in the material but by way of "idea" or "representation" in the mind of the craftsman. A house does not produce another house, but the house as existing in "idea" in the builder's mind sets him at work building, and so produces a corresponding house in brick or stone. Thus the ultimate opposition is between the "cause as matter," a passive and inert substratum of change and development and the "formal" cause which, in the sense just explained, is one with both the "efficient" or starting-point, and the "end" or goal of development. It will, of course, be seen that individual bearers of "forms" are indispensable in the theory; hence the notion ofactivityis essential to the causal relation. It is a relation between things, not between events. Aristotle has no sense of the word cause corresponding to Mill's conception of a cause as an event which is the uniform precursor of another event.
Two more remarks may be made in this connection. (1) The prominence of the notion of "end" gives Aristotle's philosophy a thorough-going "ideological" character. God and Nature, he tells us, do nothing aimlessly. We should probably be mistaken if we took this to mean that "God and Nature" act everywhere with conscious design. The meaning is rather that every natural process has a last stage in which the "form" which was to begin with present in the agent or "source of change" is fully realised in the matter in which the agent has set up the process of change. The normal thing ise.g.for animals to reproduce "their kind"; if the reproduction is imperfect or distorted, as in monstrous births, this is an exception due to the occasional presence in "matter" of imperfections which hinder the course of development, and must be regarded as "contrary to the normal course of Nature." So hybrid reproduction is exceptional and "against Nature," and this is shown by the sterility of hybrids, a sort of lesser monstrosity. Even females, being "arrested developments," are a sort of still minor deviation from principle. (2) It may just be mentioned that Aristotle has a classification of efficient causes under the three heads of Nature, Intelligence (or Man), and Chance. The difference between Nature and Man or Intelligence as efficient causes has already been illustrated. It is that in causation by Nature, such as sexual reproduction, or the assimilation of nutriment, or the conversion of one element into another in which Aristotle believed, the form which is superinduced on the matter by the agent already exists in the agent itself asitsform. The oak springs from a parent oak, the conversion of nutriment into organic tissue is due to the agency of already existing organic tissue. In the case of human intelligence or art, the "form" to be superinduced exists in the agent not ashischaracteristic form, but by way of representation, as a contemplated design. The man who builds a house is not himself a house; the form characteristic of a house is very different from that characteristic of a man, but it is present in contemplation to the builder before it is embodied in the actual house. A word may be added about the third sort of efficient causality, causation by chance. This is confined to cases which are exceptions from the general course of Nature, remarkable coincidences. It is what we may call "simulated purposiveness." When something in human affairs happens in a way which subserves the achievement of a result but was not really brought about by any intention to secure the result, we speak of it as a remarkable coincidence. Thus it would be a coincidence if a man should be held to ransom by brigands and his best friend should, without knowing anything of the matter, turn up on the spot with the means of ransoming him. The events could not have happened more opportunely if they had been planned, and yet they were not planned but merely fell out so: and since such a combination of circumstances simulating design is unusual, it is not proper to say that the events happened "in the course of Nature." We therefore say it happened by chance. This doctrine of chance has its significance for mediæval Ethics. In an age when the Protestant superstition that worldly success is proof of nearness to God had not yet been invented, the want of correspondence between men's "deserts" and their prosperity was accounted for by the view that the distribution of worldly goods is, as a rule, the work of Fortune or Chance in the Aristotelian sense; that is, it is due to special coincidences which may look like deliberate design but are not really so. (See the elaborate exposition of this in Dante,Inferno, vii. 67-97.)
Motion.--We have seen that causation, natural or artificial, requires the production in a certain "matter" of a certain "form" under the influence of a certain "agent." What is the character of the process set up by the agent in the matter and culminating in the appearance of the form? Aristotle answers that it is Motion (kinesis). The effect of the agent on the matter is to set up in it a motion which ends in its assuming a definite form. The important point to be noted here is that Aristotle regards this motion as falling wholly within the matter which is to assume the form. It is not necessary that the agent should itself be in motion, but only that it should induce motion in something else. Thus in all cases of intentional action the ultimate efficient cause is the "idea of the result to be attained," but this idea does not move about. By its presence to the mind it sets something else (the members of the body) moving. This conception of an efficient cause which, not moving itself, by its mere presence induces movement in that to which it is present, is of the highest importance in Aristotle's theology. Of course it follows that since the motion by which the transition from potentiality to actuality is achieved falls wholly within the matter acted upon, Aristotle is not troubled with any of the questions as to the way in which motion can be transferred from one body to another which were so much agitated in the early days of the modern mechanical interpretation of natural processes. Aristotle's way of conceiving Nature is thoroughly non-mechanical, and approximates to what would now be called the ascription of vital or quasi-vital characteristics to the inorganic. As, in the causality of "art" the mere presence of the "form" to be embodied in a given material to the mind of the craftsman brings about and directs the process of manufacture, so in some analogous fashion the presence of an efficient cause in Nature to that on which it works is thought of as itself constituting the "efficiency" of the cause. As Lotze phrases it, things "take note of" one another's compresence in the universe, or we might say the efficient cause and that on which it exercises its efficiency areen rapport. "Matter" is sensitive to the presence of the "efficient cause," and in response to this sensitivity, puts forth successive determinations, expands its latent tendencies on definite lines.
The name "motion" has a wider sense for Aristotle than it has for ourselves. He includes under the one common name all the processes by which things come to be what they are or cease to be what they have been. Thus he distinguishes the following varieties of "motion":generation(the coming of an individual thing into being), with its oppositedecayorcorruption(the passing of a thing out of being),alteration(change ofqualityin a thing),augmentationanddiminution(change in themagnitudeof a thing),motion through space(of which latter he recognises two sub-species, rectilineartransferenceandrotationin a circular orbit about an axis). It is this last variety, motion through space, which is the most fundamental of all, since its occurrence is involved in that of any of the other types of process mentioned, though Aristotle does not hold the thorough-going mechanical view that the other processes are only apparent, and that, as we should put it, qualitative change is a mere disguise which mechanical motion wears for our senses.
The Eternity of Motion.--Certain very important consequences follow from the conception of efficient causation which we have been describing. Aristotle has no sympathy with the "evolutionist" views which had been favoured by some of his predecessors. According to his theory of organic generation, "it takes a man to beget a man "; where there is a baby, there must have been a father. Biological kinds representing real clefts in Nature, the process of the production of a young generation by an already adult generation must be thought of as without beginning and without end. There can be no natural "evolution" of animals of one species from individuals of a different kind. Nor does it occur to Aristotle to take into account the possibility of "Creationism," the sudden coming into being of a fully fledged first generation at a stroke. This possibility is excluded by the doctrine that the "matter" of a thing must exist beforehand as an indispensable condition of the production of that thing. Every baby, as we said, must have had a father, but that father must also have been a baby before he was a full-grown man. Hence the perpetuation of unchanging species must be without beginning and without end. And it is implied that all the various processes, within and without the organism, apart from which its life could not be kept up, must be equally without beginning and without end. The "cosmos," or orderly world of natural processes, is strictly "eternal"; "motion" is everlasting and continuous, or unbroken. Even the great Christian theologians who built upon Aristotle could not absolutely break with him on this point. St. Thomas, though obliged to admit that the world was actually created a few thousand years before his own time, maintains that this can only be known to be true from revelation, philosophically it is equably tenable that the world should have been "created from all eternity." And it is the general doctrine of scholasticism that the expression "creation" only denotes the absolute dependence of the world on God for its being. When we say "God created the world out of nothing," we mean that He did not make it out of pre-existing matter, that it depends for its being on Him only; the expression is purely negative in its import.
God.--With the doctrine of the eternity of the world and the processes which make up its life we come close to the culminating theory of Aristotelian First Philosophy, its doctrine of God, as the eternal, unchanging source of all change, movement, and process. All motion is a process within matter by which the forms latent in it are brought into actual manifestation. And the process only takes place in the presence of an adequate efficient cause or source of motion. Hence the eternity of natural processes involves the existence of one or more eternal sources of motion. For, if we do not admit the existence of an unoriginated and ever-present source or sources of motion, our only alternative is to hold that the world-process is due to a series of sources of motion existing successively. But such a view would leave the unity and unbroken continuity of the world-process unaccounted for. It would give us a succession of processes, temporally contiguous, not one unbroken process. Hence we argue from the continuity of motion to its dependence on a source or sources which are permanent and present throughout the whole everlasting world-process. And when we come to the question whether there is only one such ultimate source of movement for the whole universe, or several, Aristotle's answer is that the supreme "Unmoved Mover" is one. One is enough for the purpose, and the law of parcimony forbids us to assume the superfluous. This then is the Aristotelian conception of God and God's relation to the world. God is the one supreme unchanging being to whose presence the world responds with the whole process of cosmic development, the ultimate educer of the series of "forms" latent in the "matter" of the world into actual manifestation. Standing, as He does, outside the whole process which by His mere presence He initiates in Nature, He is not himself a composite of "form" and "matter," as the products of development are. He is a pure individual "form" or "actuality," with no history of gradual development behind it. Thus He is a purely immaterial being, indispensable to the world's existence but transcending it and standing outside it.HowHis presence inspires the world to move Aristotle tries to explain by the metaphor of appetition. Just as the good I desire and conceive, without itself "moving" "moves" my appetition, so God moves the universe by being its good. This directly brings about a uniform unbroken rotation of the whole universe round its axis (in fact, the alternation of day and night). And since this rotation is communicated from the outermost "sphere" of heaven to all the lesser "spheres" between it and the immovable centre, the effects of God's presence are felt universally. At the same time, we must note that though God is the supreme Mover of the Universe, He is not regarded by Aristotle as its Creator, even in the sense in which creation can be reconciled with the eternity of the world. For the effect of God's presence is simply to lead to the development of "form" in an already existing "matter." Without God there could be no "form" or order in things, not even as much as is implied in the differentiation of matter into the four "elements," yet "primary matter" is no less than God a precondition of all that happens.
It is characteristic of Aristotle that his God is as far from discharging the functions of a Providence as He is from being a Creator. His "activity" is not, as Plato had made it, that of the great "Shepherd of the sheep." As far as the world is concerned, God's only function is to be there to move its appetition. For the rest, the unbroken activity of this life is directed wholly inward. Aristotle expressly calls it an "activity of immobility." More precisely, he tells us, it is activity of thought, exercised unbrokenly and everlastingly upon the only object adequate to exercise God's contemplation, Himself. His life is one of everlastingself-contemplation or "thinking of thought itself." Like all unimpeded exercise of activity, it is attended by pleasure, and as the activity is continuous, so the pleasure of it is continuous too. At our best, when we give ourselves up to the pure contemplative activity of scientific thought or æsthetic appreciation, we enter for a while into this divine life and share the happiness of God. But that is a theme for our chapter on theEthics.
It is a far cry from this conception of a God untroubled by care for a world to which He is only related as the object of its aspiration to the God who cares even for the fall of the sparrow and of whom it is written,Sic Deus dilexit mundum, but it was the standing task of the philosophical theologians of the Middle Ages to fuse the two conceptions. Plato's God, who, if not quite the Creator, is the "Father and Fashioner" of us all, and keeps providential watch over the world He has fashioned, would have lent Himself better to their purposes, but Plato was held by the mediæval church to have denied the resurrection of the body. The combination of Aristotle's Theism with the Theism of early Christianity was effected by exquisitely subtle logical devices, but even in St. Thomas one cannot help seeing the seams.
Nor can one help seeing in Aristotle's own doctrine the usual want of coherence between an initial anti-Platonic bias and a final reversion to the very Platonic positions Aristotle is fond of impugning. We are told at the outset that the Platonic "separate forms" are empty names, and that the real individual thing is always a composite of matter and a form which only exists "in matter." We find in the end that the source of the whole process by which "matter" becomes imbued with "form" is a being which is "pure" form and stands outside the whole development which its presence sets up. And the issue of Aristotle's warning against "poetic metaphors" is the doctrine that God moves the world by being "the object of the world's desire."