Descent of Man, chapter iii.
CHAPTER XII—FLUX AND CONSTANCY IN HUMAN NATURE
Respectable tradition that human nature is fixed.
A conception of something called human nature arises not unnaturally on observing the passions of men, passions which under various disguises seem to reappear in all ages and countries. The tendency of Greek philosophy, with its insistence on general concepts, was to define this idea of human nature still further and to encourage the belief that a single and identical essence, present in all men, determined their powers and ideal destiny. Christianity, while it transposed the human ideal and dwelt on the superhuman affinities of man, did not abandon the notion of a specific humanity. On the contrary, such a notion was implied in the Fall and Redemption, in the Sacraments, and in the universal validity of Christian doctrine and precept. For if human nature were not one, there would be no propriety in requiring all men to preserve unanimity in faith or conformity in conduct. Human nature was likewise the entity which the English psychologists set themselves to describe; and Kant was so entirely dominated by the notion of a fixed and universal human nature that its constancy, in his opinion, was the source of all natural as well as moral laws. Had he doubted for a moment the stability of human nature, the foundations of his system would have fallen out; the forms of perception and thought would at once have lost their boasted necessity, since to-morrow might dawn upon new categories and a modified a priori intuition of space or time; and the avenue would also have been closed by which man was led, through his unalterable moral sentiments, to assumptions about metaphysical truths.
Contrary currents of opinion.
Evolution
The force of this long tradition has been broken, however, by two influences of great weight in recent times, the theory of evolution and the revival of pantheism. The first has reintroduced flux into the conception of existence and the second into the conception of values. If natural species are fluid and pass into one another, human nature is merely a name for a group of qualities found by chance in certain tribes of animals, a group to which new qualities are constantly tending to attach themselves while other faculties become extinct, now in whole races, now in sporadic individuals. Human nature is therefore a variable, and its ideal cannot have a greater constancy than the demands to which it gives expression. Nor can the ideal of one man or one age have any authority over another, since the harmony existing in their nature and interests is accidental and each is a transitional phase in an indefinite evolution. The crystallisation of moral forces at any moment is consequently to be explained by universal, not by human, laws; the philosopher's interest cannot be to trace the implications of present and unstable desires, but rather to discover the mechanical law by which these desires have been generated and will be transformed, so that they will change irrevocably both their basis and their objects.
Pantheism.
To this picture of physical instability furnished by popular science are to be added the mystical self-denials involved in pantheism. These come to reinforce the doctrine that human nature is a shifting thing with the sentiment that it is a finite and unworthy one: for every determination of being, it is said, has its significance as well as its origin in the infinite continuum of which it is a part. Forms are limitations, and limitations, according to this philosophy, would be defects, so that man's only goal would be to escape humanity and lose himself in the divine nebula that has produced and must invalidate each of his thoughts and ideals. As there would be but one spirit in the world, and that infinite, so there would be but one ideal and that indiscriminate. The despair which the naturalist's view of human instability might tend to produce is turned by this mystical initiation into a sort of ecstasy; and the deluge of conformity suddenly submerges that Life of Reason which science seemed to condemn to gradual extinction.
Instability in existences does not dethrone their ideals.
Reason is a human function. Though the name of reason has been applied to various alleged principles of cosmic life, vital or dialectical, these principles all lack the essence of rationality, in that they are not conscious movements toward satisfaction, not, in other words, moral and beneficent principles at all. Be the instability of human nature what it may, therefore, the instability of reason is not less, since reason is but a function of human nature. However relative and subordinate, in a physical sense, human ideals may be, these ideals remain the only possible moral standards for man, the only tests which he can apply for value or authority, in any other quarter. And among unstable and relative ideals none is more relative and unstable than that which transports all value to a universal law, itself indifferent to good and evil, and worships it as a deity. Such an idolatry would indeed be impossible if it were not partial and veiled, arrived at in following out some human interest and clung to by force of moral inertia and the ambiguity of words. In truth mystics do not practise so entire a renunciation of reason as they preach: eternal validity and the capacity to deal with absolute reality are still assumed by them to belong to thought or at least to feeling. Only they overlook in their description of human nature just that faculty which they exercise in their speculation; their map leaves out the ground on which they stand. The rest, which they are not identified with for the moment, they proceed to regard de haut en bas and to discredit as a momentary manifestation of universal laws, physical or divine. They forget that this faith in law, this absorption in the blank reality, this enthusiasm for the ultimate thought, are mere human passions like the rest; that they endure them as they might a fever and that the animal instincts are patent on which those spiritual yearnings repose.
Absolutist philosophy human and halting.
This last fact would be nothing against the feelings in question, if they were not made vehicles for absolute revelations. On the contrary, such a relativity in instincts is the source of their importance. In virtue of this relativity they have some basis and function in the world; for did they not repose on human nature they could never express or transform it. Religion and philosophy are not always beneficent or important, but when they are it is precisely because they help to develop human faculty and to enrich human life. To imagine that by means of them we can escape from human nature and survey it from without is an ostrich-like illusion obvious to all but to the victim of it. Such a pretension may cause admiration in the schools, where self-hypnotisation is easy, but in the world it makes its professors ridiculous. For in their eagerness to empty their mind of human prejudices they reduce its rational burden to a minimum, and if they still continue to dogmatise, it is sport for the satirist to observe what forgotten accident of language or training has survived the crash of the universe and made the one demonstrable path to Absolute Truth.
All science a deliverance of momentary thought.
Neither the path of abstraction followed by the mystics, nor that of direct and, as it avers, unbiassed observation followed by the naturalists, can lead beyond that region of common experience, traditional feeling, and conventional thought which all minds enter at birth and can elude only at the risk of inward collapse and extinction. The fact that observation involves the senses, and the senses their organs, is one which a naturalist can hardly overlook; and when we add that logical habits, sanctioned by utility, are needed to interpret the data of sense, the humanity of science and all its constructions becomes clearer than day. Superstition itself could not be more human. The path of unbiassed observation is not a path away from conventional life; it is a progress in conventions. It improves human belief by increasing the proportion of two of its ingredients, attentive perception and practical calculus. The whole resulting vision, as it is sustained from moment to moment by present experience and instinct, has no value apart from actual ideals. And if it proves human nature to be unstable, it can build that proof on nothing more stable than human faculty as at the moment it happens to be.
All criticism likewise.
Nor is abstraction a less human process, as if by becoming very abstruse indeed we could hope to become divine. Is it not a commonplace of the schools that to form abstract ideas is the prerogative of man's reason? Is not abstraction a method by which mortal intelligence makes haste? Is it not the makeshift