Materialism is that method of thought which gives priority to matter, rather than to mind, in its explanations of the universe. Upon this view, material atoms constitute the ultimate and fundamental reality of which all things, rational and irrational, are but combinations and phenomena. Force is regarded as a universal and inseparable property of matter.
The element of truth in materialism is the reality of the external world. Its error is in regarding the external world as having original and independent existence, and in regarding mind as its product.
Materialism regards atoms as the bricks of which the material universe, the house we inhabit, is built. Sir William Thomson (Lord Kelvin) estimates that, if a drop of water were magnified to the size of our earth, the atoms of which it consists would certainly appear larger than boy's marbles, and yet would be smaller than billiard balls. Of these atoms, all things, visible and invisible, are made. Mind, with all its activities, is a combination or phenomenon of atoms. "Man ist was er iszt: ohne Phosphor kein Gedanke"--"One _is_ what he _eats_: without phosphorus, no thought." Ethics is a bill of fare; and worship, like heat, is a mode of motion. Agassiz, however, wittily asked: "Are fishermen, then, more intelligent than farmers, because they eat so much fish, and therefore take in more phosphorus?"
It is evident that much is here attributed to atoms which really belongs to force. Deprive atoms of force, and all that remains is extension, which = space = zero. Moreover, "if atoms _are_ extended, they cannot be ultimate, for extension implies divisibility, and that which is conceivably divisible cannot be a philosophical ultimate. But, if atoms _are not_ extended, then even an infinite multiplication and combination of them could not produce an extended substance. Furthermore, an atom that is neither extended substance nor thinking substance is inconceivable. The real ultimate is force, and this force cannot be exerted by nothing, but, as we shall hereafter see, can be exerted only by a personal Spirit, for this alone possesses the characteristics of reality, namely, definiteness, unity, and activity."
Not only force but also intelligence must be attributed to atoms, before they can explain any operation of nature. Herschel says not only that "the force of gravitation seems like that of a universal will," but that the atoms themselves, in recognizing each other in order to combine, show a great deal of "presence of mind." Ladd, Introd. to Philosophy, 269--"A distinguished astronomer has said that every body in the solar system is behaving as if it knew precisely how it ought to behave in consistency with its own nature, and with the behavior of every other body in the same system.... Each atom has danced countless millions of miles, with countless millions of different partners, many of which required an important modification of its mode of motion, without ever departing from the correct step or the right time." J. P. Cooke, Credentials of Science, 104, 177, suggests that something more than atoms is needed to explain the universe. A correlating Intelligence and Will must be assumed. Atoms by themselves would be like a heap of loose nails which need to be magnetized if they are to hold together. All structures would be resolved, and all forms of matter would disappear, if the Presence which sustains them were withdrawn. The atom, like the monad of Leibnitz, is "parvus in suo genere deus"--"a little god in its nature"--only because it is the expression of the mind and will of an immanent God.