"Definite," for example, is hardly a physical idea at all. Every motion and every arrangement of matter is definitely what it is,--a fog or an irregular scrawl, as much so as a billiard ball or a straight line. Spencer means by definiteness in a thing any character that makes it arrest our attention, and forces us to distinguish it from other things. The word with him has a human, not a physical connotation. Definite things, in his book, finally appear merely as _things that men have made separate names for_, so that there is hardly a pretence of the mechanical view being kept. Of course names increase as human history proceeds, so "definiteness" in things must necessarily more and more evolve. "Coherent," again. This has the definite mechanical meaning of resisting separation, of sticking together; but Spencer plays fast and loose with this meaning. Coherence with him sometimes means _permanence in time_, sometimes such _mutual dependence of parts_ as is realized in a widely scattered system of no fixed material configuration; a commercial house, for example, with its "travellers" and ships and cars. An honestly mechanical reader soon rubs his eyes with bewilderment at the orgy of ambiguity to which he is introduced. Every term in Spencer's fireworks shimmers through a whole spectrum of meanings in order to adapt itself to the successive spheres of evolution to which it must apply. "Integration," for instance. A definite coherence is an Integration; and examples given of integration are the contraction of the solar nebula, the formation of the earth's crust, the calcification of cartilage, the shortening of the body of crabs, the loss of his tail by man, the mutual dependence of plants and animals, the growth of powerful states, the tendency of human occupations to go to distinct localities, the dropping of terminal inflexions in English grammar, the formation of general concepts by the mind, the use of machinery instead of simple tools, the development of "composition" in the fine arts, etc., etc. It is obvious that no one form of the motion of matter characterizes all these facts. The human ones simply embody the more and more successful pursuit of certain ends.