[17] The question has been asked, What becomes of the potential energy contained in the food, if it is not converted into bodily energy? I reply, it is given off or imparted to the body as heat (not energy), but this heat is again given off by the body. The more imparted to the body, the more is again given off. We know that the body possesses a self-regulating apparatus which keeps the body, when alive, always at a constant temperature. (When dead, of course, the "corpse" cools to the temperature of the surrounding air.) The equivalence is again maintained, it will be observed, because the more heat we impart to the body the more it in turn gives off. CHAPTER IV THE HUMAN WILL IS A PHYSICAL ENERGY AN INSTRUMENT WHICH PROVES IT PART I The Facts That the human will is a definite physical energy, which can be registered by means of a scale or balance, may appear so incredible that the bare statement of the case would seem to carry with it its own refutation! Yet I firmly believe that this is a fact; that the energy of the will may be registered by means of an instrument I am about to describe; and that any one can prove this,--any one, i.e., who cares to take the time to repeat these experiments, and to try a sufficient number of subjects until the right ones be found--who are capable of affecting the balance in the manner described. Such a fact--if fact it be--is of the utmost importance to science and to philosophy; even more important and more far-reaching in its implications than may at first sight appear. Not only is the fact itself of extraordinary interest, but the very origin and structure of our universe is called into question--and shown to be capable of an interpretation very different from that usually offered by modern science. And, further, if it be true that the human will is a physical energy, we have here the discovery of a _new force_--a force just as new to science as magnetism or electricity--and vastly more interesting, since it is intimately associated with all of us, and subject to our direction, guidance, and command--a force for us to wield and manipulate--for weal or woe! It may be thought, by some, that this is no new discovery; that the human will is a physical energy is a fact of common observation; and that we all feel the liberation of this energy whenever an act of volition is performed. I may reply at once to such critics that (common sense as it may appear) this is not at all the attitude of modern psychology; and that, by _savants_ the will is not considered an energy at all, but rather a choice of actions or an effort of attention. It is a state of consciousness merely, possessing intrinsically no more energy than any other state of the kind. This may, perhaps, be made clear by the following brief quotation from James' _Psychology_: