So, too, with celestial mechanics, which had terrestrial mechanics for its parent.  The very conception of force, which underlies the whole of mechanical astronomy, is borrowed from our earthly experiences; and the leading laws of mechanical action as exhibited in scales, levers, projectiles, etc., had to be ascertained before the dynamics of the solar system could be entered upon.  What were the laws made use of by Newton in working out his grand discovery?  The law of falling bodies disclosed by Galileo; that of the composition of forces also disclosed by Galileo; and that of centrifugal force found out by Huyghens—­all of them generalisations of terrestrial physics.  Yet, with facts like these before him, M. Comte places astronomy before physics in order of evolution!  He does not compare the geometrical parts of the two together, and the mechanical parts of the two together; for this would by no means suit his hypothesis.  But he compares the geometrical part of the one with the mechanical part of the other, and so gives a semblance of truth to his position.  He is led away by a verbal delusion.  Had he confined his attention to the things and disregarded the words, he would have seen that before mankind scientifically co-ordinated any one class of phenomena displayed in the heavens, they had previously co-ordinated a parallel class of phenomena displayed upon the surface of the earth.

Were it needful we could fill a score pages with the incongruities of M. Comte’s scheme.  But the foregoing samples will suffice.  So far is his law of evolution of the sciences from being tenable, that, by following his example, and arbitrarily ignoring one class of facts, it would be possible to present, with great plausibility, just the opposite generalisation to that which he enunciates.  While he asserts that the rational order of the sciences, like the order of their historic development, “is determined by the degree of simplicity, or, what comes to the same thing, of generality of their phenomena;” it might contrariwise be asserted, that, commencing with the complex and the special, mankind have progressed step by step to a knowledge of greater simplicity and wider generality.  So much evidence is there of this as to have drawn from Whewell, in his History of the Inductive Sciences, the general remark that “the reader has already seen repeatedly in the course of this history, complex and derivative principles presenting themselves to men’s minds before simple and elementary ones.”

Even from M. Comte’s own work, numerous facts, admissions, and arguments, might be picked out, tending to show this.  We have already quoted his words in proof that both abstract and concrete mathematics have progressed towards a higher degree of generality, and that he looks forward to a higher generality still.  Just to strengthen this adverse hypothesis, let us take a further instance.  From the particular