And here I shall venture a prophecy. The new battle will be waged around psychology and philosophy. Already the lines are being drawn between the defenders of an extra-organic soul and the experimental sappers in the laboratories of biology and psychology who are seeking to show that mind and body are inseparable, that, indeed, mind is just a term for certain capacities of control exercised by the brain. The crucial character of this growing conflict, which is yet not much beyond the status of a skirmish, leaps to the eyes, as the French say. Is not even the soul to be spared the siege before which the human body fell? Is it to be placed on the dissection-table and teased apart into its component strands? Even so. The process has already begun, and far more has been accomplished than is generally known. The solution of the mind-body problem is already in the air. And, with it, will come theoretical consequences by no means secondary to those associated with the theory of evolution. With some of these consequences we shall be concerned in a later chapter. Christianity has been bound up with the letter and even with the spirit of a sacred book. Naturally, this book reflects the view of the world held by people about two thousand years ago. It contains primitive notions of the origin of things, a naive conception of the relation of the sun to the earth, a belief that demons are the cause of sickness, a conviction that souls merely inhabit bodies temporarily, and an apocalyptic idea of the end of the world in a last judgment. As we have seen, no part of this outlook was particularly unique, but it was {100} accepted by the Christian Church as inspired because it was found in the canonical writings accredited to prophets and apostles. During the Middle Ages, this biblical view of the world was united with the astronomical and physical teaching of Aristotle and hardened into a system. So intimate was this union between these cosmological elements and Christianity felt to be that an attack upon one was taken as an attack upon the whole. To doubt the primitive notions of the world and man's place therein, was to doubt the bible; and to doubt the bible as an inspired compendium of information was to doubt Christianity. For the sake of perspective, it will repay us to note the order in which these primitive ideas were attacked and replaced by more adequate ones. It will be noticed that the general cosmological setting was first reconstructed and that the growing point passed thence to the center, the nature and destiny of man. As we indicated above, the replacement of older by newer and better-founded views is proceeding most rapidly at this crucial point. Having obtained a different and vaster heaven and earth, man has turned the microscope upon himself. The suspicion is growing ever more insistent that he, also, is a natural part of this procession of things.