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and apply them to the particular cases that arise. In this path certainty attends us at every step; in the other we soon wander into the dark and intricate by-ways of uncertainty and error. The one mode is like building a house out of solid materials, and ascending by regular gradations from the foundation to the top; the other is like attempting to erect the roof and its appurtenances upon an unfinished foundation. Abstract doctrines are best illustrated by examples. In Aristotle's treatise De Calo, from the natural effect of the principle of attraction, and the circular shadow which the earth casts upon the moon during an eclipse, he deduced the inference that the earth is a sphere, contrary to the opinion of other philosophers of his time; and moreover, that it is not a very extensive sphere from the circumstance, that those stars which are perceptible to the observer, in one degree of latitude, entirely disappear, when he is removed a few degrees farther to the north or south. Here we have a speci. men of a complete and an imperfect induction from facts, which at the same time that it displays the penetration of the Stagyrite, exhibits also the tendency of the greatest minds to rush precipitately into error, when they release themselves from the restraints of a chaste and rigorous investigation. The circumstance mentioned by Aristotle, that those stars which are perceptible to the observer in one degree of latitude, entirely disappear when he is removed a few degrees farther to the north or south, shows by irresistible force of argument, that the earth is not a very extensive sphere; and the consideration urged by him also in favour of the sphericity of the earth, that during an eclipse it casts upon the moon a circular shadow, is one of the best, if not the very best proof, of which the science, even of the present day, is in possession, in confirmation of that doctrine. But upon the principles of Aristotle, that the earth must be a sphere because all bodies are attracted towards the centre, and its shadow upon the moon is circular, it ought to have been a
perfect globe, whereas subsequent discoveries of science, have shown that it is not so, but a spheroid, or flatted at the poles. Here we see that Aristotle rushed too precipitately to his axioma generale, the earth is a perfect globe; and had he proceeded, as is usually done, to form out of this proposition his axiomata media, as for example, that all bodies around the Earth's surface are equally remote from the centre, the degrees of latitude at the poles are equal to those at the equator, he would immediately have fallen in his calculations into the grossest errors.
The truth is, that this very propensity, from a few particular instances to leap to general conclusions, to which the human mind finds so powerful a temptation, in the relief which they afford it from the fatigue of investigation, is the bane of philosophy, and the productive cause of all those idle theories that have been broached at different periods, and which, after glittering for a while upon the scene, and attracting the gaze of mankind, have then vanished from the view, and sunk into the gulf of oblivion.
Does, then, this philosophical regimen throw us under such rigorous restraints, that we are to be absolutely and peremptorily prohibited from framing any theories, or making any efforts to establish systems, however verisimilar they may appear, and however courtenanced by facts, from an apprehension that subsequent discoveries may detect their fallacy, and facts afterwards elicited may contradict them? By no means. A few simple facts may lead to the suggestion of a true theory, but that thecry should never be received as true, until substantiated by sufficient proof.
Newton, it is said, from reflecting on that remarkable circumstance of the tendency of all bodies to the centre, was led to ask himself, why may not this property of attraction which occasions this result extend itself to the moon, planets, and even to the sun himself? And that this train of reflection led him on to that discovery, which it is probable, is justly regarded as the greatest ever made by man. It is to be remarked, however, that he did not assume it as a fact, that the principle of attraction, as it is found upon our globe, extends its influence throughout the solar system, until by irrefragable reasoning he had demonstrated the truth of it. We are told, that when it first suggested itself to him, he undertook to prove it, but finding himself embarrassed by difficulties which were insuperable, he for a time abandoned it as untenable, until from a more extensive acquaintance with mathematical science, it again occurred to him that it was true, and commencing the investigation anew with those farther lights he had obtained, he found the proof satisfactory: In this consisted the difference between the systein of Newton and that of Des Cartes, Leibnitz and others; the one is susceptible of strict demonstration, the others are hypotheses assumed without proof; and although they may serve to explain many of the phenomena, yet being unsubstantiated by fact and argument, must ever be regarded as the visionary schemes of ingenious men, rather than the legitimate productions of nature, and the faithful interpretations of her oracular voice. A few facts, therefore, may very properly lead to the conception of a general theory; but that theory is not to be admitted except it be demonstrated, not only by a few, but by an ample induction of facts. Harvey is said to have received the hint of the circulation of the blood, from remarking the nice and curious adjustment of the valves in the veins, that prevent the return of the blood as it passes into the heart; but he did not consider his doctrine as entitled to the attention of philosophers, until he had shown it to be true by repeated experiments with microscopes, and other methods. Lord Bacon makes a distinction between experience and experimenting, the one being considered as consisting in an observation of those appearances which vature, without any exertion on our part, spontaneously exhibits to
our view; the other, in active exertions made by us to go in pursuit of phenomena.
Enough has now been alleged to enable us to decide, without much difficulty, it is presumed, that question which has been lately raised, whether the modern school in its plan of philosophical investigation, has not arrogated to itself a merit above that of the ancient, to which it is not entitled, or in other words, whether Aristotle was not acquainted with the inductive method of lord Bacon. Dr. Gillies, the intelligent and able translator of the Moral and Political Philosophy of Aristotle, in his analysis of his works, roundly and confidently asserts that he was, and that while the illustrious Englishman was closely copying the works of the Stagyrite, he had not the candor and ingenuousness to acknowledge it, but rather indulges himself in many harsh and illiberal criticisms of the Greek. I am inclined to believe that if Dr. Gillies had studied the works of Bacon, with the same care and attention as he had those of Aristotle, and had taken pains to enter fully into the views of the former, in reference to his new mode of inquiry, he would not have done him so much injustice, but have come to a very different conclusion. I consider the method of induction as one of the sublimest hints, that ever entered into the mind of man. It is impossible to say, that had not this method been suggested by its author, it would not very naturally have presented itself to some other fortunate genius, since science was undoubtedly tending towards that result at the time; and the insufficiency of the old philosophy having been ascertained after a fair trial, a current was arising, which flowed strongly towards the invention and introduction of the new. Roger Bacon, the inquisitive and able predecessor of the Chancellor, and who proved himself worthy of the name which he bore, we know was so frequent and successful in experimenting as to obtain for himself the honourable appellation of the magician; and in an ignorant and credulous age, an age that could believe every thing but what was true, to expose himself to
persecution on account of his researches. Des Cartes, although, not averse from hypothesis, rejected the dogmas of the schools, and recommended and cultivated the study of nature. But notwithstanding, science at this time was evidently verging towards a reformation, who can say how long it would have been before philosophers would have gotten into the right way, had not that luminoles mind appeared that pointed out to them the true path to knowledge, recommended them to pursue it with all the graces of eloquence and the force of erudition, and rendered them enamoured of the prospects of those great rewards, which would accrue to them from their successful prosecution of it? Let not the Englishman, therefore, be denied the praise which he has so justly merited. On the other hand, it is not to be denied, that we can scarcely turn over a page of the works of Aristotle, which have any reference to nature, but we find an immediate appeal to fact and experience. It is certainly true, what has been happily said of him, that if he did not interrogate nature, he listened to her with unremitted attention. His metaphysics, his moral and political philosophy, his treatise De Cælo, de anima, his mechanical questions, and in truth, all those of his works in which it was his purpose to investigate nature, fully attest the truth of this observation. How, then, can it be said that he was not apprised of the method of induction? The mystery is readily solved. It is a very different thing occasionally to have had recourse to experience and observation, in order to confirm his doctrines, and to have comprehended this method as the only legitimate vehicle for the advanceinent of science. We have be. fore seen that as soon as man passes from the simplest perceptions of his nature, and begins to make inquiry concerning the operations of those objects upon each other with which he is daily conversant, he is obliged to have recourse to this instrument, in order to arrive at any of those maxims which ordinarily influence his conduct in life. The lessons