Man is a part of Nature, not something contrasted with Nature. His thoughts and his bodily movements follow the same laws that describe the motions of stars and atoms. The physical world is large compared with Man――larger than it was thought to be in Dante’s time, but not so large as it seemed a hundred years ago. Both upward and downward, both in the large and in the small, science seems to be reaching limits. It is thought that the universe is of finite extent in space, and that light could travel round it in a few hundred millions of years. It is thought that matter consists of electrons and protons, which are of finite size, and of which there are only a finite number in the world. Probably their changes are not continuous, as used to be thought, but proceed by jerks, which are never smaller than a certain minimum jerk. The laws of these changes can apparently be summed up in a small number of very general principles, which determine the past and the future of the world when any small section of its history is known.
Physical science is thus approaching the stage when it will be complete, and therefore uninteresting. Given the laws governing the motions of electrons and protons, the rest is merely geography――a collection of particular facts telling their distribution throughout some portion of the world’s history. The total number of facts of geography required to determine the world’s history is probably finite; theoretically, they could all be written down in a big book to be kept at Somerset House, with a calculating machine attached, which, by turning a handle, would enable the inquirer to find out the facts at other times than those recorded. It is difficult to imagine anything less interesting, or more different from the passionate delights of incomplete discovery. It is like climbing a high mountain and finding nothing at the top except a restaurant where they sell ginger-beer, surrounded by fog but equipped with wireless. Perhaps in the time of Ahmes the multiplication-table was exciting.
Of this physical world, uninteresting in itself, Man is a part. His body, like other matter, is composed of electrons and protons, which, so far as we know, obey the same laws as those not forming part of animals or plants. There are some who maintain that physiology can never be reduced to physics, but their arguments are not very convincing and it seems prudent to suppose that they are mistaken. What we call our “thoughts” seem to depend upon the organization of tracks in the brain in the same sort of way in which journeys depend upon roads and railways. The energy used in thinking seems to have a chemical origin; for instance, a deficiency of iodine will turn a clever man into an idiot. Mental phenomena seem to be bound up with material structure. If this be so, we cannot suppose that a solitary electron or proton can “think”; we might as well expect a solitary individual to play a football match. We also cannot suppose that an individual’s thinking survives bodily death, since that destroys the organization of the brain, and dissipates the energy which utilized the brain-tracks.
God and immortality, the central dogmas of the Christian religion, find no support in science. It cannot be said that either doctrine is essential to religion, since neither is found in Buddhism. (With regard to immortality, this statement in an unqualified form might be misleading, but it is correct in the last analysis). But we in the West have come to think of them as the irreducible minimum of theology. No doubt people will continue to entertain these beliefs, because they are pleasant, just as it is pleasant to think ourselves virtuous and our enemies wicked. But for my part I cannot see any ground for either. I do not pretend to be able to prove that there is no God. I equally cannot prove that Satan is a fiction. The Christian God may exist; so may the Gods of Olympus, or of ancient Egypt, or of Babylon. But no one of these hypotheses is more probable than any other: they lie outside the region of even probable knowledge, and therefore there is no reason to consider any of them. I shall not enlarge upon this question, as I have dealt with it elsewhere.
See my Philosophy of Leibniz, Chapter XV.
The question of personal immortality stands on a somewhat different footing. Here evidence either way is possible. Persons are part of the everyday world with which science is concerned, and the conditions which determine their existence are discoverable. A drop of water is not immortal; it can be resolved into oxygen and hydrogen. If, therefore, a drop of water were to maintain that it had a quality of aqueousness which would survive its dissolution, we should be inclined to be sceptical. In like manner we know that the brain is not immortal, and that the organized energy of a living body becomes, as it were, demobilized at death, and therefore not available for collective action. All the evidence goes to show that what we regard as our mental life is bound up with brain-structure and organized bodily energy. Therefore it is rational to suppose that mental life ceases when bodily life ceases. The argument is only one of probability, but it is as strong as those upon which most scientific conclusions are based.
There are various grounds upon which this conclusion might be attacked. Psychical research professes to have actual scientific evidence of survival, and undoubtedly its procedure is, in principle, scientifically correct. Evidence of this sort might be so overwhelming that no one with a scientific temper could reject it. The weight to be attached to the evidence, however, must depend upon the antecedent probability of the hypothesis of survival. There are always different ways of accounting for any set of phenomena, and of these we should prefer the one which is antecedently least improbable. Those who already think it likely that we survive death will be ready to view this theory as the best explanation of psychical phenomena. Those, who, on other grounds, regard this theory as unplausible will seek for other explanations. For my part, I consider the evidence so far adduced by psychical research in favour of survival much weaker than the physiological evidence on the other side. But I fully admit that it might at any moment become stronger, and in that case it would be unscientific to disbelieve in survival.
Survival of bodily death is, however, a different matter from immortality: it may only mean a postponement of psychical death. It is immortality that men desire to believe in. Believers in immortality will object to physiological arguments, such as I have been using, on the ground that soul and body are totally disparate, and that the soul is something quite other than its empirical manifestations through our bodily organs. I believe this to be a metaphysical superstition. Mind and matter alike are for certain purposes convenient terms, but are not ultimate realities. Electrons and protons, like the soul, are logical fictions: each is really a history, a series of events, not a single persistent entity. In the case of the soul, this is obvious from the facts of growth. Whoever considers conception, gestation, and infancy cannot seriously believe that the soul is an indivisible something, perfect and complete throughout this process. It is evident that it grows like the body, and that it derives both from the spermatozoon and from the ovum, so that it cannot be indivisible. This is not materialism: it is merely the recognition that everything interesting is a matter of organization, not of primal substance.
Metaphysicians have advanced innumerable arguments to prove that the soul must be immortal. There is one simple test by which all these arguments can be demolished. They all prove equally that the soul must pervade all space. But as we are not so anxious to be fat as to live long, none of the metaphysicians in question have ever noticed this application of their reasonings. This is an instance of the amazing power of desire in blinding even very able men to fallacies which would otherwise be obvious at once. If we were not afraid of death, I do not believe that the idea of immortality would ever have arisen.
Fear is the basis of religious dogma, as of so much else in human life. Fear of human beings, individually or collectively, dominates much of our social life, but it is fear of nature that gives rise to religion. The antithesis of mind and matter is, as we have seen, more or less illusory; but there is another antithesis which is more important――that, namely, between things that can be affected by our desires and things that cannot be so affected. The line between the two is neither sharp nor immutable――as science advances, more and more things are brought under human control. Nevertheless there remain things definitely on the other side. Among these are all the large facts of our world, the sort of facts that are dealt with by astronomy. It is only facts on or near the surface of the earth that we can, to some extent, mould to suit our desires. And even on the surface of the earth, our powers are very limited. Above all, we cannot prevent death, although we can often delay it.
Religion is an attempt to overcome this antithesis. If the world is controlled by God, and God can be moved by prayer, we acquire a share in omnipotence. In former days, miracles happened in answer to prayer; they still do in the Catholic Church, but Protestants have lost this power. However, it is possible to dispense with miracles, since Providence has decreed that the operation of natural laws shall produce the best possible results. Thus belief in God still serves to humanize the world of nature, and to make men feel that physical forces are really their allies. In like manner immortality removes the terror from death. People who believe that when they die they will inherit eternal bliss may be expected to view death without horror, though, fortunately for medical men, this does not invariably happen. It does, however, soothe men’s fears somewhat, even when it cannot allay them wholly.
Religion, since it has its source in terror, has dignified certain kinds of fear, and made people think them not disgraceful. In this it has done mankind a great disservice: all fear is bad, and ought to be overcome not by fairy tales, but by courage and rational reflection. I believe that when I die I shall rot, and nothing of my ego will survive. I am not young, and I love life. But I should scorn to shiver with terror at the thought of annihilation. Happiness is none the less true happiness because it must come to an end, nor do thought and love lose their value because they are not everlasting. Many a man has borne himself proudly on the scaffold: surely the same pride should teach us to think truly about man’s place in the world. Even if the open windows of science at first make us shiver after the cosy indoor warmth of traditional humanizing myths, in the end the fresh air brings vigour, and the great spaces have a splendour of their own.
The philosophy of nature is one thing, the philosophy of value is quite another. Nothing but harm can come of confusing them. What we think good, what we should like, has no bearing whatever upon what is, which is the question for the philosophy of nature. On the other hand, we cannot be forbidden to value this or that on the ground that the non-human world does not value it, nor can we be compelled to admire anything because it is a “law of nature.” Undoubtedly we are part of nature, which has produced our desires, our hopes and fears, in accordance with laws which the physicist is beginning to discover. In this sense we are part of nature; in the philosophy of nature, we are subordinated to nature, the outcome of natural laws, and their victims in the long run.
The philosophy of nature must not be unduly terrestrial; for it, the earth is merely one of the smaller planets of one of the smaller stars of the Milky Way. It would be ridiculous to warp the philosophy of nature in order to bring out results that are pleasing to the tiny parasites of this insignificant planet. Vitalism as a philosophy, and evolutionism, show, in this respect, a lack of sense of proportion and logical relevance. They regard the facts of life, which are personally interesting to us, as having a cosmic significance, not a significance confined to the earth’s surface. Optimism and pessimism, as cosmic philosophies, show the same naïve humanism: the great world, so far as we know it from the philosophy of nature, is neither good nor bad, and is not concerned to make us either happy or unhappy. All such philosophies spring from self-importance, and are best corrected by a little astronomy.
But in the philosophy of value the situation is reversed. Nature is only a part of what we can imagine; everything, real or imagined, can be appraised by us, and there is no outside standard to show that our valuation is wrong. We are ourselves the ultimate and irrefutable arbiters of value, and in the world of value Nature is only a part. Thus in this world we are greater than Nature. In the world of values, Nature in itself is neutral, neither good nor bad, deserving of neither admiration nor censure. It is we who create value, and our desires which confer value. In this realm we are kings, and we debase our kingship if we bow down to Nature. It is for us to determine the good life, not for Nature――not even for Nature personified as God.
