A theory is an argument—when it is not a fallacy—and an argument, we have seen, consists of two parts. There is the matter of fact requiring explanation, and the antecedent knowledge which is used to illustrate it. Of these the precedent is the more important, and it is no valid objection to a criticism that the person who offers it knows less about the case than the theorist. The critic may be in possession of a better precedent, which the theorist has failed to notice, perhaps from a too exclusive attention to the case.

In the question before us the case is Mechanical or Inorganic Energy. It is not an object, but an inference from the knowledge of our personal mental energy. This latter is the only energy we really perceive. But we find in objects, or associated with the perception of them, a power capable of assisting or of opposing our efforts—hence we conclude it is something of the same nature as our own power. We cannot well avoid that inference, and there is no apparent reason why we should try to avoid it.

So far science and philosophy are at one, but here they part company. Philosophy consistently endows Nature with sentiency also, for we never—to our certain knowledge—meet with energy without sentiency, and we have no right to transfer one attribute without the other.

Although science is indebted to the assimilation of organic and inorganic—Nature explained by Man—for the first notion of external energy, no sooner is the notion formed than the argument is discarded, and external energy is declared to be entirely destitute of an organic and mental character. How then is it to be further explained? To what shall it now be likened?

In the materialistic scheme all things are supposed to be resolved into matter and force. Matter is conceived as a self-existent substance, indestructible, &c. It is better known than force, for material things can be directly perceived whereas force is imaginary all the time. Under these circumstances it is natural though illogical to treat force as a species of matter. With only two things left in the universe, the better known of the two will be used to explain the less known, if an explanation is considered indispensable. Force is accordingly brought as a 'case' under matter as a 'precedent,' and is concluded to be indestructible because matter is believed to be indestructible; and when energy appears to be wasted the inference is that it has simply withdrawn from view, like an object that has ceased to be perceived and may be perceived again. That seems to be the evolution of the scientific notion of inorganic energy.

This theorem is fallacious in two respects. There is no such matter as science imagines. Matter is a general idea formed by the study of material objects, which are states of consciousness excited by noumenal contact. It is the average object—a mere affection or formation of the observing mind. We are the makers of matter. Such an idea cannot be said to be indestructible: in a sense it is destroyed in an individual when it is forgotten or inactive; it would certainly be destroyed if all minds ceased to form it. Thus the precedent in the scientific theory of force is itself false.

Then energy is not in the least like matter—either the matter of science or that of philosophy. The energy we really know is a unique experience—not a general idea, nor anything analogous to a phenomenal object; so that even if the proposed precedent were true in itself, it is not applicable to the case. To complete our knowledge of external energy we must go back to that comparison which first suggested to us that there is external energy, namely, the comparison of living man with living nature.

If this is not a correct account of the derivation of the notion that cosmic energy is indestructible, let conservationists tell us what is the parallel on which they are arguing. Here is a blank theorem for completion—

x is indestructible
Cosmic energy is a
sort of x
it must therefore be considered indestructible

Matter, as we have seen, is not x. Human energy is not x. Our individual power—so far as experience informs us—is destroyed in the using. A day's work exhausts us, and we have to pass into the condition called sleep to be refilled. It is sleep, not food, that refreshes the mind. Food restores the bodily tool we have been working with—puts a fresh edge on the chisel,—but it does not recuperate the power that wields the tool.