"E Pur Si Muove!"
The temptation of the dramatic effect of this phrase has been too strong for writers who should have known better than to give it currency. In the declamation of a school exhibition, we are not surprised to find it; but from a serious historian it comes with a bad grace. M. Ponsard has, of course, preserved it in his drama.
It is simply fable, and like the "Up, Guards, and at them!" of Lord Wellington, "un de ces mots de circonstance inventés après coup." [Footnote 144]
[Footnote 144: "One of those impromptus composed at leisure."]
"Unstable, timorous, equivocating, and supple," says Philarète Chasles, "he never had the heart to exclaim, 'E pur si muove!'" He never exhibited that heroical resistance which has been attributed to him.
The penitential shirt or sack is also fabulous, notwithstanding even so distinguished a man as Cousin speaks of Galileo as "forcé d'abjurer á genoux, en chemise, son plus beau titre de gloire." [Footnote 145]
[Footnote 145: "Forced to abjure on his knees, and clad in a shirt, his noblest title to greatness."]
Value Of The Decree.
A few words—and but few are needed—as to the common assertion that the Catholic Church, claiming infallibility in matters of faith, decided the doctrine of the earth's immobility to be a truth affirmed in the Scriptures. Granting the decree of the Inquisition in the case of Galileo to have been all that is claimed against it, it was, after all, nothing but a decree of the Inquisition; no more, no less.
And first, what was the Inquisition?
The Inquisition forms no permanent or essential part of the organization of the Catholic Church. It was always a purely local tribunal, and the original appointment of its officers asquaesitores fidei, or inquisitors, seems to have been designed to prevent civil wars on the score of religion. The prevailing sentiment as well as the positive jurisprudence of the middle ages approved the punishment of heresy by temporal penalties.Indeed, such principles, abhorrent to us, seem to have come down out of the so-called dark ages far toward our own time. For full confirmation of this statement, you may read John Calvin's treatise in defence of persecuting measures, in which he maintains the lawfulness of putting heretics to death; and for illustration, you may peruse the account of his treatment of Castellio and Servetus, who found Calvin's reasoning of such peculiar strength that they did not survive its application; or his letter to Somerset, (1548:) "You have two kinds of mutineers: the one are a fanatical people, who, under color of the gospel, would set all to confusion; the others are stubborn people in the superstition of the Antichrist of Rome.These altogether do deserve to be well punished by the sword." (See Froude'sHistory of England, vol. v.) Charming impartiality!
More than a hundred years afterward, Calvin's followers embodied his doctrine in their solemn confession of faith, wherein they say (Westminster Confession, ch. xxiii.) that "the civil magistrate hath authority, and it is his duty, to take order, that all blasphemies and heresies be suppressed."
Although inquisitors existed in Italy from the time of Innocent IV., their authority was so rarely exercised that it was scarcely known until Paul III., in the year 1545, organized the Congregation of the Inquisition, consisting of six cardinals. To these were added two more by Pius V. They formed a strictly ecclesiastical tribunal, charged with matters regarding the integrity of faith throughout the world; their duty being to examine and censure erroneous propositions, condemn and proscribe bad books, inflict ecclesiastical censures on clergymen convicted of error, and exercise a superintendence over the local tribunals of faith.
It still exists, acts, and exercises its ecclesiastical attributes.
But however powerful to suppress opinion or to exact obedience the Inquisition might be within the limits of its own special jurisdiction, we have never yet heard that any decree of any inquisition ever determined a question of faith, or, in other words, ever attempted to usurp the functions of a general council.
Even Riccioli, the original source, up to within a few years, of all accounts of the trial and sentence of Galileo, and himself one of the strongest theological opponents of the theory of the earth's motion, expressly protests against the assertion that any declaration whatever had been made on the subject by the church itself. He says: "The Sacred Congregation of Cardinals, taken apart from the Supreme Pontiff, does not make propositions to be of faith,even though it should actually define them to be of faith, or the contrary ones heretical. Wherefore, since no definition upon this matter has as yet issued from the Supreme Pontiff, nor from any council directed and approved by him, it is not yet of faith that the sun moves and the earth stands still by force of the decree of the Congregation; but at most and alone, by the force of the sacred Scriptures to those to whom it is morally evident that God has revealed it. Nevertheless, Catholics are bound, in prudence and obedience, at least so far as not to teach the contrary."
And yet, plain as is this distinction, men of professedly theological acquirements, for the sake of inflicting a wound on the church, systematically ignore it whenever they have "a point" to make with the Galileo story.
And the distinction is not only plain at the present day, but was expressly made at the time of Galileo's trial. "It was not in the power of the holy office to declare it (Galileo's scientific theory) or any other doctrine heresy; it would take an OEcumenical Council for that." (Letter of September 4th, 1632: Cardinal Magalotti to Galileo.) Even Descartes, six months after the trial, remarks that the decision of the Inquisition had received the ratification of neither pope nor council.
The Torture.
The relators of the torture fable ask us to believe that an old man bending under the weight of seventy years, after undergoing imprisonment and mental anguish, suffered thepeine forte et dureof torture on the 21st of June, and on the next day was capable of remaining more than an hour on his knees to receive his sentence, and then, unaided, arose, stamped his foot, and thundered out, "E pur si muove!" Truly a vigorous performance, but not more hardy than the story which relates it.
No; these fables can no longer have place in history; and we know positively that Galileo, who, on the evening of June 24th, after his three days' detention at the holy office, (the sentence of imprisonment being immediately commuted by the pope,) was conducted by Niccolini to the Villa Medici, and who, on the 6th of July, old as he was, was able to walk four miles without inconvenience, could not have been tortured on the 21st of June.
"Those who undertake," says the German Protestant Von Reumont, "to accuse the Inquisition on this point, are forced to have recourse to fiction."
Lord Brougham, after an examination of the case, says, in his Analytical View of the Principia, that "the supposition of Galileo having been tortured is entirely disproved by Galileo's own account of the lenity with which he was treated."
Biot dismisses the matter thus: "II y a là une réunion d'invraisemblances qui ne permet pas de concevoir raisonnablement un soupçon pareil." [Footnote 146]
[Footnote 146: "There is here such a conjunction of improbabilities as to exclude all reasonable possibility of such a suspicion."]
Galileo survived his sentence eight years. Is it credible that, during that long period spent in intimate personal intercourse and literary correspondence with his friend, no word or hint of complaint of such an outrage as torture should have escaped his lips?
Castelli was constantly with him to the hour of his death, and heard no whisper of it.
In August, 1638, writing to Bernegger, Galileo could boast that neither the freedom nor the vigor of his spirit was repressed.
Three months before his death, with the certainty of its approach, he sent for Torricelli, and spent long hours in unreserved discourse with him. Not a word of torture!
Finally, in his last letter, just three weeks before his death, to Beccherini, he bewails his endurances and his troubles in a spirit that could not and did not fail to unseal his lips for everything he had to say in the spirit of complaint; but here, too, not a word of torture!
The majority of the French feuilletonists on the Ponsard drama manifest disappointment at not finding any torture, and straightway seek solace in such reflections as, "Ainsi, Galilée ne fut point mis à la torture; on en a aujourd'hui la pleine certitude."! [Footnote 147]
[Footnote 147: "Thus, then, Galileo was not put to the torture. Of that we now have the fullest certainty."]
But the feuilletonist wants to know if the persecutions, bitterness, and vexation of every kind to which Galileo was subjected were not the equivalent of physical torture?
And what, then, does he take to be the equivalent of the irony, sarcasm, ingratitude, and insult gratuitously heaped upon Urban, the kind friend and liberal benefactor of Galileo?
No reasonable doubt can now exist as to the fact that it was not Galileo's assertion of the hypothesis of the earth's rotation that brought him into trouble. It was his intemperance of language, impatience of wise counsel, disregard of sacred obligations, violation of solemn promises, and above all, his insane perversity in dragging the scriptural element into the controversy. Of the scores of distinguished adherents, disciples, advocates, and professors of the heliocentric doctrine, Galileo alone gave annoyance and created difficulty.
To the extent of examining and discussing the question scientifically, the freedom at Rome was perfect. But when the point was reached when it was gratuitously thrust into collision with Scripture, a degree of demonstration was needed that could not be produced.
After The Trial.
To complete the chronological statement of events, it is only necessary to add that on the 6th of July Galileo left Rome for Sienna, where he remained with Archbishop Piccolomini, one of his most intimate friends, until the month of December. He then returned to his own home at Arcetri, near Florence.
It was here he received the oft-described and well-known visit of Milton, then in the prime of youth. In 1638, he transferred his residence to Florence, where he occupied himself with scientific pursuits, his negotiation with Holland for the use of his discovery concerning the longitude, the publication of his bookDialoghi delle Nuove Scienzeat Leyden, (1638,) correspondence with scientific men, and visits from his friends.
He died on the 8th of January, 1642, in the seventy-eighth year of his age.
"The noblest eye," wrote his friend Father Castelli, announcing his death, "which nature ever made, is darkened; an eye so privileged and gifted with such rare powers that it may truly be said to have seen more than the eyes of all that are gone, and to have opened the eyes of all that are to come."
We now pass to the consideration of the exact condition of
The Scientific Question
as it existed in 1633, leaving, of course, aside all discussion of its theological or scriptural connection.
Without going back so far as Pythagoras, the new system in 1633 was not original with Galileo, nor even with Copernicus, who is said to have received the germ of his new doctrine at Bologna from the hypothesis of Dominicus Maria on the variability of the axis of the earth; and it would be most interesting, did space allow, to review the intellectual struggles of the predecessors (ad astra) of the Polish priest with a theory they felt to be true, but were powerless to demonstrate even to themselves.
Among these men were:
1. The great mystical theologian, Richard of St. Victor, who described the true method of physical inquiry in terms which Francis Bacon might have adopted. "It would not be easy at the present day," says Dr. Whewell, (Philosophy of Discovery, pp. 52-53,) "to give a better account of the object of physical science."
2. Celius Calcagnini, (born 1479,) who published (Tiraboschi saysdivolgò, which may or may not mean simply printing) a work in which he endeavored to prove "quod coelum stet, terra autem moveatur."
3. Cardinal Cusa, sometimes called Nicholas the Cusan, an intellectual giant of his time, the highest expression, probably, of the active mental movement that marked the 15th century. He was equally distinguished in science, in letters, and in philosophy, and in 1436, at the Council of Basle, proposed the reform of the calendar afterward carried out by the pope. His knowledge of astronomy was, for his time, profound, and he asserted and published that "the sun is at rest, the earth moves," ("istam terram in veritate moveatur.") [Footnote 148]
[Footnote 148: "That heaven is motionless, but that the earth moves."]
4. Novara, the preceptor of Copernicus; for it is certain that Copernicus found his new doctrine in Italy.
5. Jerome of Tallavia, whose papers are said to have fallen into the hands of Copernicus.
6. Leonardo da Vinci, who, in 1510, connected his theory of bodies with the earth's motion, "showing," as Whewell says, "that the heliocentric doctrines were fermenting in the minds of intelligent men, and gradually assuming clearness and strength."
Although Da Vinci constructed no system of explanation, he nevertheless held the motion of the earth, as appears from one of his manuscripts of the year 1500.
Some light may be thrown upon the actual condition of astronomical science during the Galileo period by a short statement of the arguments most in vogue between
Ptolemaists And Copernicans,
and of what the latter had to present in the way of proof.
The Copernicans contended generally for the greater simplicity of their system, and the incredibility of the enormous velocity which the sphere of the fixed stars must have if the ancient system be true. To this it was answered that God doeth wonders without number.
But the earth would corrupt and putrefy without motion, whereas the heavens are incorruptible. To which the answer was ready that wind would give sufficient motion.
But the most movable part of man is underneath, since he walks with his feet; whence the most unworthy part of the universe, the earth, should be movable.
Objected that, if the earth moves, the head of a man moves faster than his feet.
But again, "Rest is nobler than motion, and therefore ought to belong to the sun, the noble body."
Replied to, "For the same reason, the moon and all the planets ought to rest."
Again, "The lamp of the world ought to be in the centre." Answered by, "A lamp is frequently hung up from a roof to enlighten the floor."
"Can we fancy," asked the Copernicans, "that God has not acted on a scheme so impressive and so beautiful as ours?"
"Can we fancy," replied their opponents, "that this earth is constantly in motion, which we feel to be the stablest of all things? that our senses are given to deceive us? that during the greater part of our lives we cling to the earth with our head downward?"
Finally, the Copernicans were utterly silenced by the unanswerable argument of throwing up a stone.
"Would they please explain," was asked of them, "why, if the earth moved, the stone, being thrown directly upward, should fall on the spot from which it was thrown?"
The Copernicans were silent, for they could assign no reason. "In the sixteenth century," says Professor De Morgan, "the wit of man could not imagine how, if the earth moved, a stone thrown directly upward would tumble down upon the spot it was thrown from." It was reserved for a man who was born on the same day Galileo died to furnish the reason.
Astronomy In 1633.
To one seeking for a demonstrated system, astronomy was then a hopeless chaos of irreconcilable facts—an impenetrable jungle of conflicting theories. That such was the actual condition of the science in Galileo's day, we find fully recognized and aptly described by a distinguished English Protestant, a great name in English literature, who, himself "an exact mathematician" and astronomer, was most active in research and observation precisely during the period of Galileo's greatest fame. We refer to Burton, author of the celebratedAnatomy of Melancholy.
This remarkable book was written by Burton during the years extending from 1614 to 1621, when the first edition was published. The subsequent editions of 1624, 1628, 1632, and 1638 were all issued during the life of the author, who died in 1639, a succession of years precisely covering the period of Galileo's controversies and trials; and yet its author, vicar of St. Thomas and rector of Segrave, (Church of England as by law established,) who never misses an opportunity ever so slight of giving Catholicity a thrust or a stab, makes 'mere mention' of Galileo's condemnation thus: "These paradoxes of the earth's motion which the Church of Rome hath lately condemned as heretical."
The truth is, that in that day the course pursued by the Congregation at Rome was generally approved even by Protestants. In their eyes, nothing but a paradox was condemned. Having exhausted all his proof, where does Galileo leave our exact English mathematician, who evidently read and knew of everything published on the subject in his day?
Why, Burton speaks of "that main paradox of the earth's motion now so much in question," and devotes five full pages to a presentation of all the theories then current, giving Galileo's as of no more value than the others! He thus sums them up:
"One offends against natural philosophy, another against optic principles, a third against mathematical, as not answering to astronomical observations. One puts a great space between Saturn's orb and the eighth sphere, another too narrow. In his own hypothesis, he makes the earth as before the universal centre, the sun to the five upper planets; to the eighth sphere he ascribes diurnal motion; eccentrics and epicycles to the seven planets, which hath been formerly exploded; and so,dum vitant stulti vitia, in contraria currant, [Footnote 149] as a tinker stops one hole and makes two, he corrects them, and doth worse himself: reforms some and mars all. In the mean time, the world is tossed in a blanket amongst them, they hoist the earth up and down like a ball, make it stand and go at their pleasures: one saith the sun stands; another, he moves; a third comes in, taking them all at rebound, and lest there should any paradox be wanting, he finds certain spots and clouds in the sun. …
[Footnote 149: "While they avoid one mistake, they run into the contrary."]
And thus they disagree amongst themselves, old and new, irreconcilable in their opinions; thus Aristarchus, thus Hipparchus, thus Ptolemaeus, thus Albateginus, thus Alfraganus, thus Tycho, thus Ramerus, thus Raeslinus, thus Fracastorius, thus Copernicus and his adherents," etc.
Not a word here of Galileo.
The whole chapter is very curious, and will well repay the trouble of reading. See pages 323 to 329, London edition.
Notwithstanding his condition of paradox as seen by disinterested men of science, Galileo claimed three propositions as settled:
First. The system was demonstrated.Second. He demonstrated it.Third. His was the honor of furnishing the demonstration from the flux and reflux of the tides.
To these three propositions it is replied that the system was not at that day demonstrated by Galileo or by any one else, and that his tidal argument was worthless.
Indeed, a sufficient answer is found in the simple statement, in which all astronomers must certainly accord, that before the time of Sir Isaac Newton there was nothing to make the Copernican system more plausible and reasonable than the Ptolemaic theory, because the English astronomer first explained the one law on which planetary revolutions depended.
The theory of the earth's rotation was, in 1633, barely a matter of induction—strong, it is true, yet nothing more than induction. Strong, if the two arguments taken from the phases of Venus and the satellites of Jupiter are duly weighed; but weak without them.
The discovery of the satellites of Jupiter was called by Herschel "the holding turn of the Copernican system," but Galileo had no conception of its value; he passed it by as insignificant, and settled down complacently upon the flux and reflux of the tides as the crowning proof. To this proof, and to no other, he clung during the citation of 1616.
Astronomers express great surprise that Galileo makes no mention of the belts of Jupiter, although they are visible with the aid of the smallest glass.
Zucchi, a Jesuit, was the first to note them in Rome, (1630.) In like manner, the discovery of the spots on the sun do not appear to have benefited him in ascertaining the sun's rotation. "Galilée," says Arago, "n'a pas non plus la moindre apparence de droit à la découverte du mouvement de rotation du soleil. On a vu les taches; aucune conséquence de cette observation n'est indiquée." [Footnote 150]
[Footnote 150: "Neither has Galileo the slightest apparent claim to the discovery of the sun's rotation. The spots are observed, but no deduction is drawn from the observation."]
The oversights concerning Jupiter are the more remarkable as Galileo's labors in investigation of the satellites were long and exhausting. It is only within a few years that this fact has been ascertained through the discovery by Professor Alberi of a long series of observations of the satellites of Jupiter, with tables and ephemerides drawn up for the purpose of comparing the longitude.
These manuscripts, described as a "mighty monument of his labors"—and doubtless they must be, for all his calculations were necessarily made without the aid of logarithms—were found in the Pitti Palace library, and are published by Alberi in the fifth volume of his magnificent edition of Galileo's work.
Herschel says that the science of astronomy was yet in its infancy at the period of Newton's death, and after all that Newton had done for it. What, then, must we think of its condition in the hands of Galileo, with his toy telescope, his fallacious tidal theory, and his necessary ignorance of the great discoveries that followed him?
In 1618, he published hisTheory of the Tides. In 1623, he again puts it forward in a letter to Ingulfi; and finally devotes the fourth and last day of theDialogueto the development of the same argument.
Nay, more, in this dialogue he scoffs at the simplicity of Kepler, who has had the temerity, after his (Galileo's) satisfactory explanation of the phenomena, to listen to such stuff as the occult properties of the moon's influence on the tides, and other like puerilities! We find by reference to a marginal note in the Padua edition of theDialoguesat the Astor Library, that a prelate, Girolamo Borro, wrote a pamphlet setting forth the theory of the moon's influence on the tides, and Simplicio is made to quote him: "E ultimamente certo prelato ha publicato un tratello dove dice che la luna vagando per il cielo attrae e solleva verso di se un cumulo d'acqua, il quale va continualmente seguitanclo," etc. [Footnote 151]
[Footnote 151: "And lately a certain prelate has published a pamphlet, in which he says that the moon, traversing the heavens, attracts and draws after her a mass of water which continually follows," etc.]
Here Sagredo stops him abruptly, saying, "For heaven's sake, Signor Simplicio, let us have no more of that; for it is a mere loss of time to listen to it, as well as to confute it, and you simply do injustice to your judgment by regarding such or similar puerilities."
No wonder, as Bailli says, "la foule d'astronomes etaient centre!" [Footnote 152]
[Footnote 152: "The mass of astronomers were of the contrary opinion."]
Galileo died in profound ignorance of the true tidal theory, and the credit of pointing it out is ascribed by Mr. Drinkwater to the College of Jesuits at Coimbra.
But more than all this, Galileo had already made great mistakes, and committed errors that were publicly rectified by his contemporaries.
Thus, one of the most remarkable astronomical phenomena of the age, the three comets of 1618, was totally misunderstood by Galileo, who pronounced them atmospheric meteors.
The Jesuit Grassi, in his treatiseDe Tribus Cometis, (1618,) had the merit of explaining what had baffled Galileo, who at first held them to be planets moving in vast ellipses around the sun.
Charity For All.
In referring to these errors of Galileo, Laplace says that it would be unjust to judge him with the same rigor as one who should refuse at present to believe the motion of the earth, confirmed by the numerous discoveries made in astronomy since that period.
And John Quincy Adams, in a memorable discourse delivered at Cincinnati in 1843, says of Tycho Brahe, (who maintained that the earth is immovable in the centre of the universe,) "The religion of Tycho in the encounter with his philosophy obtained a triumph honorable to him, but erroneous in fact."
All which maybe very true; and if Laplace and Mr. Adams err at all, they err certainly on the side of charity and kindness.
But are we to have one standard of justice for one class of men, and a far different one for another class? Is that which is excusable in an Italian and honorable in a Danish astronomer, ignorant, bigoted, and vile in a cardinal? Or is there any good reason why that which in Denmark is a "triumph of religion" should in Rome become a "victory of ignorance"?
Tycho Brahe, in his day a profound astronomer, noble and wealthy, devoting his whole life to science in unremitting observation of the heavens, with the aid of the most complete and costly apparatus in existence at the time, might surely be supposed to have reached a safer conclusion than an ignorant churchman.
And how, moreover, could such a churchman be expected to pin his faith to the sleeve of an astronomer like Galileo, whose errors and blunders were frequent and serious, and who, when in his conjectures he stumbled upon the truth, could hardly distinguish it from error, and was therefore as likely to give a bad as a good reason for his doctrine? Or, as M. Biot admirably expresses it, "si l'état imparfait de cette science l'exposait ainsi à donner parfois de mauvaises raisons comme bonnes, il faut pardonner à ses adversaires de n'avoir pas pu toujours distinguer les bonnes des mauvaises." [Footnote 153]
[Footnote 153: "If the imperfection of this science thus made him liable to give bad reasons for good, his adversaries should surely be pardoned for not always being able to distinguish the good from the bad."]
Anti-Catholic controversialists will persist in endowing the Galileo period with an amount of astronomical and physical science that then had no existence. Intelligent, industrious, and learned the cardinals of Galileo's day certainly were; but it is absurd to attribute to them or to their times a knowledge of the Copernican system, as afterward explained by Kepler, Newton, and two centuries of men of science. Kepler'sLaws of the Universewere not published until 1619, and even then, and long years afterward, who could possibly apply them until Newton's discoveries gave them force and authority?
If our modern sciolists, who prattle so much about "the ignorant and bigoted court of Rome," knew enough to be a little modest, they might take to heart the reflection of the great English essayist, and remember it is no merit of theirs that prevents them from falling into the mistakes of a cardinal "whose pens they are not worthy to mend." It certainly was asking a great deal of men that they should abandon settled tradition, the teachings of authority, the evidence of their senses, and the warrant of Scripture, as they understood it, to embrace a strange, startling, and incomprehensible doctrine, in no degree better off in demonstration than the old one. Even the weight of scientific authority was in their favor, as is readily seen when we look at the relative strength of
Copernican and Anti-Copernican.
Tycho Brahe was far from being alone in his dissent from Copernicus and Galileo. Saving only the bright spot made by Kepler and a few of his disciples, all Germany, France, and England were still in comparative darkness, and it is difficult to believe that at the period of Galileo's trial there were as many avowed Copernicans in all Europe together as in the single city of Rome.
In Germany, the new system was almost universally rejected, and Wolfgang Menzel, in hisHistory of Germany, speaks of it as "die unter den Protestanten in Deutschland noch iminer bezweifelte Wahrheit des Copernikanischen Welt-systems." [Footnote 154:]
[Footnote 154: "The even yet (by German Protestants) contested truth of the Copernican system."]
The frontispiece to Riccioli'sAlmagestum Novum, Astor Library copy, published in 1651, presents a curious illustration of the prevalent estimate of the new doctrines. A figure with a pair of balances is seen weighing the Tychonian against the Copernican system, and the truth of the former is shown by its overwhelming preponderance. Riccioli cites fourteen authors who up to that day had written in favor of the Copernican theory, and thirty-seven who had written against it. He adduces seventy arguments in favor of the Tychonian, and can find but forty-nine in support of the Copernican; consequently, the mere force of numbers proves the improbability of the latter.
In France, Ramus, the Huguenot Royal Professor at Paris, utterly refused the doctrine ten years after the death of Galileo.
Thomas Lydiat, a distinguished English astronomer of his day, and so good a scholar as to come victorious out of a controversy on chronology with Scaliger, openly opposed the Copernican system in hisPraelectio Astronomica, (1605.) In fact, no man of astronomical acquirements of that day, and for more than fifty years afterward, dared risk the success of a book by putting in it anything favoring the Copernican theory.
Even as late as 1570, we find John Dee, an English Copernican, who, despairing of the ignorant prejudice around him, would not so much as hint at the existence of the system in his preface toBillingsley's Euclid.
In Great Britain, the system was discredited by the illustrious Gilbert. Milton, too, seems to have doubted it. Its most active opponent was Alexander Rosse, a voluminous Scotch writer, alluded to inHudibras.
Hume tells us Lord Bacon "rejected the system of Copernicus with the most positive disdain." [Footnote 155] It is but fair to say, though, that this statement, like too many of Hume's, should be qualified. It is true that in hisDe AugmentisBacon says that the absurdity and complexity of the Ptolemaic system has driven men to the doctrine of the earth's motion, which is clearly false, "quod nobis constat falsissimum esse;" but, on the other hand, in theNovum Organum, he distinctly speaks of the question of the earth's motion as one to be examined. Now, the latter work, although published before, was written after theDe Augmentis, which is less serious and argumentative than theNovum Organum.
[Footnote 155: Macaulay should have said, "theory of Copernicus," instead of "theory of Galileo." Bacon never credited Galileo with a system, and did not hold his scientific merits in much esteem.]
Even in 1705, the Hon. E. Howard published in London a work entitledCopernicans of all Sorts Convicted.
In 1806, Mercier, a Frenchman, wrote to prove "l'impossibilité des systèmes de Copernic et de Newton;" and even so recently as 1829 an individual was found so retrograde as to publish a work entitled TheUniverse as it is; wherein the Hypothesis of the Earth's Motion is Refuted,etc., by W. Woodley.
The Undemonstrated Problem.
And now, having spied out the nakedness of the astronomic land throughout Europe, let us return for a moment to the scientific position of the tribunal that tried Galileo.
What solid proof was presented to it? None whatever. And those familiar with the history of astronomy will readily recognize the fact that, so far from seeing in the new opinion a scientific novelty, they recognized in it substantially the old hypothesis of Pythagoras, which, after obtaining credit for more than five hundred years, was triumphantly displaced by the Ptolemaic theory; which was that the earth is a solid globe at rest in the centre of the universe, with the various planetary bodies revolving in larger and larger circles, according to the order of their distances.
The new doctrine had not even the form of a system:
"'Twas neither shape nor feature."
Indeed, as has been truly said, it was nothing more than a paradox for the support of which its authors had to draw upon their own resources.
High astronomical authority, Délambre, thus sums up the utter absence of proof, in Galileo's time, of the theory of the earth's rotation:
"What solid reason could induce the ancients to disbelieve the evidence of their senses? Yes, and even despite the immense progress which astronomy has subsequently made, have the moderns themselves been able to allege any one direct proof of the diurnal motion of the earth, previous to the voyage of Richer to Cayenne, where he was obliged to shorten his pendulum? Have they been able to discover one positive demonstration to the point, to prove the annual revolution of the earth, before Roemer measured the velocity of light, and Bradley had observed and calculated the phenomena of the aberration?
"Previous to these discoveries, and that of universal gravitation, were not the most decided Copernicans reduced to mere probabilities? Were they not obliged to confine themselves to preaching up the simplicity of the Copernican system, as compared with the absurd complexity of that of Ptolemy?"
What "solid reason," indeed, could be given? But Galileo in his presumption did not consider himself reduced to "mere probabilities," and, relying on his tidal fallacies and unexplained phenomena, sought to pass hypothesis for dogma, and hisipse dixitfor demonstration.
Of the great discoveries enumerated by Délambre, Galileo was necessarily ignorant, and we must insist upon the fact that the cardinals and the Inquisition were equally ignorant of them.
There was, in reality, no astronomical science in Galileo's time worth speaking of, except as we compare it with the astronomy that preceded it, which is the only fair test of its value. Compared with what Ptolemy knew, it was twilight.
Compared with what we know, it was darkness.
It is moderate to say that in 1633 astronomy was in its infancy. To all that was then known, add Kepler's magnificent labors, Torricelli's discovery, Newton's principle of gravitation, and all the English astronomer did for science—come down to the year 1727, in which he died, and what was the condition of astronomical science even then?
Herschel has told us: "The legacy of research which was left us by Newton was indeed immense. To pursue through all its intricacies the consequences of the law of gravitation; to account for all the inequalities of the planetary movements, and the infinitely more complicated and to us more important ones of the moon; and to give, whatNewton himself certainly never entertained a conception of,a demonstration of the stability and permanence of the system under all the accumulated influence of its internal perturbations; this labor and this triumph were reserved for the succeeding age, and have been shared in succession by Clairault, D'Alembert, Euler, Lagrange, and Laplace. Yet so extensive is this subject, and so difficult and intricate the purely mathematical inquiries to which it leads, thatanother century may yet be required to go through the task."
The Legacy Of Research
left by Newton may truly be called "immense." And Herschel does well to modify his statement as to the "triumph," and postpone it yet another century.
For it must be borne in mind that no astronomical system is a strictly verifiable fact. The circulation of the blood is a verifiable fact, and it has been verified. No announcement of the discovery of a new demonstration of its truth could now attract any attention on account of its merits as proof.
Not so as to the earth's motion. The proofs of that have always been merely referential and cumulative. The final, the crowning point of demonstration has never been made, and probably never can be reached. Who can say that he ever saw the earth move? Hence it is that every successive item of cumulative evidence is hailed with pleasure and excitement. Thus was it with Torricelli's, Newton's, Richer's, Roemer's, and Bradley's discoveries; thus with all the brilliant inventions in mechanics by means of which the illustration and explanations of these discoveries became possible—explanations which, after all, not one man in a thousand can understand.
Post-Galilean Astronomy.
A few words in addition to what we have already said concerning the great discoveries made since Galileo's time, and we close.
Three of these discoveries, without which the Copernican theory as to demonstration would be but little better off than the Ptolemaic, merit special mention. They are:
First. The Newtonian theory of gravitation.Second. The discovery of the shortened pendulum, showing the diurnal motion of the earth.Third. The velocity and aberration of light, showing the annual motion.
It is scarcely necessary to enter into any detail concerning the so generally known, great, and universal principle of gravitation.
The Shortened Pendulum.
Up to the year 1672, no doubt had been entertained of the spherical figure of the earth, and, as a consequence, of the equality of all the degrees of the meridian; so that one being known, the whole circumference was determined.
In that year, the French Academy of Sciences, then occupied in the measurement of an arc in the meridian, sent the astronomer Richer to Cayenne, on the coast of South America, to make observations of the sun's altitude.
In the course of these observations he was surprised to find that a superior clock, furnished with a pendulum which vibrated seconds, was found to lose nearly two minutes and a half a day.
The astonishment created by the report of this fact in France was very great, particularly after the accuracy of the clock had been fully tested.
Other scientific men then visited different points on the coasts of Africa and South America, and were convinced of the absolute necessity of shortening the pendulum to make it vibrate seconds in those latitudes.
The phenomenon was explained by Newton in the Third Book of hisPrincipia(1687)—see p. 409et seq., American edition—where he shows it to be a necessary consequence of the earth's rotation on its axis, and of the centrifugal force created by it. That force, in modifying the gravity, gives to the earth an oblate spheroidal figure, more elevated at the equator than on the poles, and makes bodies fall and pendulums vibrate more slowly in low than in high latitudes.
There is, unfortunately, such a thing as national jealousy even in science, and to such a motive only can we ascribe the fact that Newton's explanation was not accepted in France until presented by Huyghens, several years afterward, in a different and less accurate form.
The Velocity And Aberration Of Light.
In the entire range of scientific literature, there are few chapters of greater interest than those which recount the rise and gradual development of all the principles involved in the triumphant demonstration of these two beautiful discoveries.
They admirably illustrate the total ignorance of Galileo concerning a problem upon which he experimented with utter failure, as also the slow pace of scientific progress, and the necessity of the co-operative efforts of many men and many sciences to perfect it.
It required the genius and research of Roemer, Bradley, Molyneux, Arago, Fizeau, Foucault, and Struve, joined to the patient experiment and mechanical skill of Bréguet, Bessel, and Graham—the labor of all these men extending through a period of one hundred and ninety years (1672 to 1862)—to complete its demonstration.
And first, as to the velocity of light. In 1672, Roemer, a Danish astronomer residing in France, began observations on the satellites of Jupiter and their eclipses, which resulted in the discovery of progressive transmission of light and the determination of the value of its velocity. Up to his day, it had almost become a fixed principle that the passage of light through space was absolutely instantaneous.
From the time of Galileo, an immense mass of exact calculations of the eclipses of the first satellite of Jupiter had been accumulating, and Roemer found that at certain times the satellite came out of the shadow later, and at other times sooner, than it should have done, and this variation could not be accounted for on any known principles. Remarking that it always came too late from the shadow when the earth in its annual movement was at more than its mean distance from Jupiter, and too soon when it was at less, he formed the conjecture that light requires an appreciable time to traverse space.
Becoming satisfied of the truth of his theory, he, in September, 1676, announced to the French Academy of Sciences that an emersion of the first satellite, to take place, on the 16th of November following, would occur ten minutes later than it should according to ordinary calculation.
The event verified his prediction. Nevertheless, doubters and cavillers abounded, and Roemer's theory was not accepted without dispute. It was claimed that the delays and accelerations in the immersions and emersions, instead of being attributed to change of position of the observer, and to the progressive transmission of light, might be regarded as indicating a real perturbation in the movement of the satellite, due to a cause not yet discovered.