FORE:Modern admirers of Aristotle labour to prove that his errors were inevitable, and belonged more to his age than to himself; that without the mechanical appliances of modern times science could not be cultivated with any hope of success. But what are we to say when we find that on one point after another the true explanation had already been surmised by Aristotles predecessors or contemporaries, only to be scornfully rejected by Aristotle himself? Their hypotheses may often have been very imperfect, and supported by insufficient evidence; but it must have been something more than chance which always led him wrong when they were so often right. To begin with, the infinity of space is not even now, nor will it ever be, established by improved instruments of observation and measurement; it is deduced by a very simple process of reasoning, of which Democritus and others were capable, while Aristotle apparently was not. He rejects the idea because it is inconsistent with certain very arbitrary assumptions and definitions of his own, whereas he should have313 rejected them because they were inconsistent with it. He further rejects the idea of a vacuum, and with it the atomic theory, entirely on priori grounds, although, even in the then existing state of knowledge, atomism explained various phenomena in a perfectly rational manner which he could only explain by unmeaning or nonsensical phrases.195 It had been already maintained, in his time, that the apparent movements of the heavenly bodies were due to the rotation of the earth on its own axis.196 Had Aristotle accepted this theory one can imagine how highly his sagacity would have been extolled. We may, therefore, fairly take his rejection of it as a proof of blind adherence to old-fashioned opinions. When he argues that none of the heavenly bodies rotate, because we can see that the moon does not, as is evident from her always turning the same side to us,197 nothing is needed but the simplest mathematics to demonstrate the fallacy of his reasoning. Others had surmised that the Milky Way was a collection of stars, and that comets were bodies of the same nature as planets. Aristotle is satisfied that both are appearances like meteors, and the aurora borealiscaused by the friction of our atmosphere against the solid aether above it. A similar origin is ascribed to the heat and light derived from the sun and stars; for it would be derogatory to the dignity of those luminaries to suppose, with Anaxagoras, that they are formed of anything so familiar and perishable as fire. On the contrary, they consist of pure aether like the spheres on which they are fixed as protuberances; though314 how such an arrangement can co-exist with absolute contact between each sphere and that next below it, or how the effects of friction could be transmitted through such enormous thicknesses of solid crystal, is left unexplained.198 By a happy anticipation of Roemer, Empedocles conjectured that the transmission of light occupied a certain time: Aristotle declares it to be instantaneous.199As a universal philosophy, the theory of Development,428 like every other modern idea, has only been permitted to manifest itself in combination with different forms of the old scholasticism. The whole speculative movement of our century is made up of such hybrid systems; and three, in particular, still divide the suffrages of many thinking men who have not been able entirely to shake off the influence of reactionary ideas. These are the systems of Hegel, of Comte, and of Mr. Herbert Spencer. In each, the logic and metaphysics inherited from Greek thought are variously compounded with the new science. And each, for that very reason, serves to facilitate the transition from one to the other; a part analogous to that played among the Greeks themselves by the vast constructions of Plato and Aristotle, or, in an age of less productivity, by the Stoic and Alexandrian philosophies.
FORE:The philosophical affinities of the new science were not exhausted by the atomistic analysis of Democritus and the regulative method of Aristotle. Platonism could hardly fail to benefit by the great impulse given to mathematical studies in the latter half of the sixteenth century. The passionate love of its founder for geometry must have recommended him as much to the most advanced minds of the period as his religious mysticism had recommended him to the theologians of the earlier Renaissance. And the increasing ascendency of the heliocentric astronomy, with its splendid defiance of sense and opinion, was indirectly a triumph for the philosophy which, more than any other, had asserted the claims of pure reason against both. We see this distinctly in Galileo. In express adhesion to Platonism, he throws his teaching into a conversational form, endeavouring to extract the truth from his opponents rather than convey it into their minds from without; and the theory of reminiscence as the source of demonstrative knowledge seems to meet with his approval.549 He is always ready with proofs drawn from observation and experiment; but nothing can be more in Platos spirit, nothing more unlike Aristotle and Bacon, than his encomium on the sublime genius of Aristarchus and Copernicus for having maintained a rational hypothesis against what seemed to be the evidence of their senses.550 And he elsewhere observes how much less would have been the glory of Copernicus had he known the experimental verification of his theory.551