In approaching this physiological problem of death we must point out the individual character of this organic phenomenon. By death we understand simply the definitive cessation of the vital activity of the individual organism, no matter to which category or stage of individuality the organism in question belongs. Man is dead when his own personality ceases to exist, whether he has left offspring that they may continue to propagate for many generations or not. In a certain sense we often say that the minds of great men (in a dynasty of eminent rulers, for instance, or a family of talented artists) live for many generations; and in the same way we speak of the “soul” of a noble woman living in her children and children’s children. But in these cases we are dealing with intricate phenomena of heredity, in which a microscopic cell (the sperm-cell of the father or the egg-cell of the mother) transmits certain features to offspring. The particular personalities who produce those sexual cells in thousands are mortal beings, and at their death their personal psychic activity is extinguished like every other physiological function.
A number of eminent zoologists—Weismann being particularly prominent—have recently defended the opinion that only the lowest unicellular organisms, the protists, are immortal, in contradistinction to the multicellular plants and animals, whose bodies are formed of tissues. This curious theory is especially based on the fact that most of the protists multiply without sexual means, by division or the formation of spores. In such processes the whole body of the unicellular organism breaks up into two or more equal parts (daughter cells), and each of these portions completes itself by further growth until it has the size and form of the mother cell. However, by the very process of division the individuality of the unicellular creature has been destroyed; both its physiological and its morphological unity have gone. The view of Weismann is logically inconsistent with the very notion of individual—an “indivisible” entity; for it implies a unity which cannot be divided without destroying its nature. In this sense the unicellular protophyta and protozoa are throughout life physiological individuals, just as much as the multicellular tissue-plants and animals. A sexual propagation by simple division is found in many of the multicellular species (for instance, in many cnidaria, corals, medusæ, etc.); the mother animal, the division of which gives birth to the two daughter animals, ceases to exist with the segmentation. “The protozoa,” says Weismann, “have no individuals and no generations in the metazoic sense.” I must entirely dissent from his thesis. As I was the first to introduce the title of metazoa, and oppose these multicellular, tissue-forming animals to the unicellular protozoa (infusoria, rhizopods, etc.), and as I was the first to point out the essential difference in the development of the two (the former from germinal layers, and the latter not), I must protest that I consider the protozoa to be just as mortal in the physiological (and psychological) sense as the metazoa; neither body nor soul is immortal in either group. The other erroneous consequences of Weismann’s notion have been refuted by Moebius (1884), who justly remarks that “every event in the world is periodic,” and that “there is no source from which immortal organic individuals might have sprung.”
When we take the idea of immortality in the widest sense, and extend it to the totality of the knowable universe, it has a scientific significance; it is then not merely acceptable, but self-evident, to the monistic philosopher. In that sense the thesis of the indestructibility and eternal duration of all that exists is equivalent to our supreme law of nature, the law of substance (see [chap. xii]). As we intend to discuss this immortality of the cosmos fully later on, in establishing the theory of the persistence of matter and force, we shall not dilate on it at present. We pass on immediately to the criticism of that belief in immortality which is the only sense usually attached to the word, the immortality of the individual soul. We shall first inquire into the extent and the origin of this mystic and dualistic notion, and point out, in particular, the wide acceptance of the contradictory thesis, our monistic, empirically established thanatism. I must distinguish two essentially different forms of thanatism—primary and secondary; primary thanatism is the original absence of the dogma of immortality (in the primitive uncivilized races); secondary thanatism is the later outcome of a rational knowledge of nature in the civilized intelligence.
We still find it asserted in philosophic, and especially in theological, works that belief in the personal immortality of the human soul was originally shared by all men—or, at least, by all “rational” men. That is not the case. This dogma is not an original idea of the human mind, nor has it ever found universal acceptance. It has been absolutely proved by modern comparative ethnology that many uncivilized races of the earliest and most primitive stage had no notion either of immortality or of God. That is true, for instance, of the Veddahs of Ceylon, those primitive pygmies whom, on the authority of the able studies of the Sarasins, we consider to be a relic of the earliest inhabitants of India;[22] it is also the case in several of the earliest groups of the nearly related Dravidas, the Indian Seelongs, and some native Australian races. Similarly, several of the primitive branches of the American race, in the interior of Brazil, on the upper Amazon, etc., have no knowledge either of gods or immortality. This primary absence of belief in immortality and deity is an extremely important fact; it is, obviously, easy to distinguish from the secondary absence of such belief, which has come about in the highest civilized races as the result of laborious critico-philosophical study.
Differently from the primary thanatism which originally characterized primitive man, and has always been widely spread, the secondary absence of belief in immortality is only found at a late stage of history: it is the ripe fruit of profound reflection on life and death, the outcome of bold and independent philosophical speculation. We first meet it in some of the Ionic philosophers of the sixth century B.C., then in the founders of the old materialistic philosophy, Democritus and Empedocles, and also in Simonides and Epicurus, Seneca and Plinius, and in an elaborate form in Lucretius Carus. With the spread of Christianity at the decay of classical antiquity, athanatism, one of its chief articles of faith, dominated the world, and so, amid other forms of superstition, the myth of personal immortality came to be invested with a high importance.
Naturally, through the long night of the Dark Ages it was rarely that a brave free-thinker ventured to express an opinion to the contrary: the examples of Galileo, Giordano Bruno, and other independent philosophers, effectually destroyed all freedom of utterance. Heresy only became possible when the Reformation and the Renaissance had broken the power of the papacy. The history of modern philosophy tells of the manifold methods by which the matured mind of man sought to rid itself of the superstition of immortality. Still, the intimate connection of the belief with the Christian dogma invested it with such power, even in the more emancipated sphere of Protestantism, that the majority of convinced free-thinkers kept their sentiments to themselves. From time to time some distinguished scholar ventured to make a frank declaration of his belief in the impossibility of the continued life of the soul after death. This was done in France in the second half of the eighteenth century by Voltaire, Danton, Mirabeau, and others, and by the leaders of the materialistic school of those days, Holbach, Lamettrie, etc. The same opinion was defended by the able friend of the Materialists, the greatest of the Hohenzollerns, the monistic “philosopher of Sans-souci.” What would Frederick the Great, the “crowned thanatist and atheist,” say, could he compare his monistic views with those of his successor of to-day?
Among thoughtful physicians the conviction that the existence of the soul came to an end at death has been common for centuries: generally, however, they refrained from giving it expression. Moreover, the empirical science of the brain remained so imperfect during the last century that the soul could continue to be regarded as its mysterious inhabitant. It was the gigantic progress of biology in the present century, and especially in the latter half of the century, that finally destroyed the myth. The establishment of the theory of descent and the cellular theory, the astounding discoveries of ontogeny and experimental physiology—above all, the marvellous progress of the microscopic anatomy of the brain, gradually deprived athanatism of every basis; now, indeed, it is rarely that an informed and honorable biologist is found to defend the immortality of the soul. All the monistic philosophers of the century (Strauss, Feuerbach, Büchner, Spencer, etc.) are thanatists.
The dogma of personal immortality owes its great popularity and its high importance to its intimate connection with the teaching of Christianity. This circumstance gave rise to the erroneous and still prevalent belief that the myth is a fundamental element of all the higher religions. That is by no means the case. The higher Oriental religions include no belief whatever in the immortality of the soul; it is not found in Buddhism, the religion that dominates thirty per cent. of the entire human race; it is not found in the ancient popular religion of the Chinese, nor in the reformed religion of Confucius which succeeded it; and, what is still more significant, it is not found in the earlier and purer religion of the Jews. Neither in the “five Mosaic books,” nor in any of the writings of the Old Testament which were written before the Babylonian Exile, is there any trace of the notion of individual persistence after death.
The mystic notion that the human soul will live forever after death has had a polyphyletic origin. It was unknown to the earliest speaking man (the hypothetical homo primigenius of Asia), to his predecessors, of course, the pithecanthropus and prothylobates, and to the least developed of his modern successors, the Veddahs of Ceylon, the Seelongs of India, and other distant races. With the development of reason and deeper reflection on life and death, sleep and dreams, mystic ideas of a dualistic composition of our nature were evolved—independently of each other—in a number of the earlier races. Very different influences were at work in these polyphyletic creations—worship of ancestors, love of relatives, love of life and desire of its prolongation, hope of better conditions of life beyond the grave, hope of the reward of good and punishment of evil deeds, and so forth. Comparative psychology has recently brought to our knowledge a great variety of myths and legends of that character; they are, for the most part, closely associated with the oldest forms of theistic and religious belief. In most of the modern religions athanatism is intimately connected with theism; the majority of believers transfer their materialistic idea of a “personal God” to their “immortal soul.” That is particularly true of the dominant religion of modern civilized states, Christianity.
As everybody knows, the dogma of the immortality of the soul has long since assumed in the Christian religion that rigid form which it has in the articles of faith: “I believe in the resurrection of the body and in an eternal life.” Man will arise on “the last day,” as Christ is alleged to have done on Easter morn, and receive a reward according to the tenor of his earthly life. This typically Christian idea is thoroughly materialistic and anthropomorphic; it is very little superior to the corresponding crude legends of uncivilized peoples. The impossibility of “the resurrection of the body” is clear to every man who has some knowledge of anatomy and physiology. The resurrection of Christ, which is celebrated every Easter by millions of Christians, is as purely mythical as “the awakening of the dead,” which he is alleged to have taught. These mystic articles of faith are just as untenable in the light of pure reason as the cognate hypothesis of “eternal life.”