It would be not merely superfluous but ridiculous to explain here at length how far the individual human consciousness depends upon the organization of the body, how it comes gradually to birth according as the brain receives impressions from without, how it is temporally interrupted during sleep, swoons, and other accidents, and how everything leads us to the rational conjecture that death carries with it loss of consciousness. And just as before our birth we were not, nor have we any personal pre-natal memory, so after our death we shall no longer be. This is the rational position. Rationalism--and by rationalism I mean the doctrine that abides solely by reason, by objective truth--is necessarily materialist. And let not idealists be scandalized thereby. The truth is--it is necessary to state it clearly--that what we call materialism means for us nothing else but the doctrine which denies the immortality of the individual soul, the persistence of personal consciousness after death. In another sense it may be said that, since we know what spirit is, and since matter is for us no more than an idea, materialism is idealism. In fact, and as regards our problem--the most vital, the only really vital problem--it is all the same to say that everything is matter as to say that everything is idea, or everything energy, or what you please. Every monist system will always seem to us materialist. The immortality of the soul is saved only by the dualist systems--those which teach that human consciousness is something substantially distinct and different from other manifestations of phenomena. And reason is naturally monist. For it is the function of reason to understand and explain the universe, and in order to understand and explain it, it is in no way necessary for the soul to be an imperishable substance. For the purpose of understanding and explaining our psychic life, for psychology, the hypothesis of the soul is unnecessary. All the attempts to substantivate consciousness, making it independent of extension--it will be remembered that Descartes opposed thought to extension--are but sophistical subtleties intended to establish the rationality of faith in the immortality of the soul. It is sought to give the value of objective reality to that which does not possess it, to that of which the reality exists only in thought. And the immortality that we crave is a phenomenal reality, it is a continuation of this life. From whatever side we look at it, it is always found that reason confronts our longing for personal immortality and contradicts it. And in strict truth, reason is the enemy of life. All that is vital is anti-rational, and all that is rational is anti-vital, for reason is essentially sceptical.