THE NEW SCHAFF-HERZOG
abstract idea or reason as that which really is or becomes, and nature as only a necessary but transient phase in the process of development. With Heraclitus evolution meant the return of all things into the primal principle followed by a new worlddevelopment; with Hegel it was an eternal process of thought, giving no answer to the question as to the end of historical development.
While Heraclitus had laid down his doctrine of eternal becoming rather by intuition than on the ground of experience, and the entire evolutionary process of Hegel had
4. Lamarck and Darwin.
been expressly conceived as based on pure thought, Darwin's epoch-making doctrine rested upon a vast mass of ascertained facts. He was, of course, not the first to lay down the origin of species one from another as a formal doctrine. Besides those predecessors of his to whom allusion has already been made, two others may be mentioned here: his father, Erasmus Darwin, who emphasized organic variability; and still more Lamarck, who denied the immutability of species and forms, and claimed to have demonstrated by observation the gradual development of the animal kingdom. What is new in Charles Darwin is not his theory of descent, but its confirmation by the theory of natural selection and the survival of the fittest in the struggle for existence. Thus a result is brought about which corresponds as far as possible to a rational end in a purely mechanical process, without any cooperation of teleological principles, without any innate tendency in the organisms to proceed to a higher stage. This theory postulates in the later organisms deviations from the earlier ones, and that these deviations, in so far as they are improvements, perpetuate themselves and become generic marks of differentiation. This, however, imports a difficulty, since the origin of the first of these deviations is inexplicable. The differentia of mankind, whom Darwin, led by the force of analogy, deduces from a species of apes, consists in intellect and moral qualities, but comes into existence only by degrees. The moral sensibilities develop from the original social impulse innate in man; this impulse is an effort to secure not so much individual happiness as the general welfare.
It would be impossible to name here all those who, in different countries, have followed in Darwin's footsteps, first in the biological 5. Haeckel, field and then in those of psychology, Guyau6' etmcs' sociology, and religion. They have carried his teaching further in several directions, modifying it to some extent and making it fruitful, while positivism has not seldom come into alliance with it. In Germany Ernst Haeckel must be mentioned with his biogenetic law, according to which the development of the individual is an epitome of the history of the race, and with his less securely grounded notion of the world-ether as a creative deity. In France Alfred Fouill6e worked out a theory of idea-forces, a combination of Platonic idealism with English (though not specifically Darwinian) evolutionism. Marie- Jean Guyau understood by evolution a life led according to the fundamental law that the most
intensive life is also the most extensive. He develops his ethics altogether from the facts of the social existence of mankind, and his religion is a universal sociomorphism, the feeling of the unity of man with the entire cosmos.
The most careful and thorough development of the whole system took place in England. For a
6 Herbert long time '* WaS rePresented princi- Spencer. Pallv bv the work of Herbert Spencer, who had come out for the principle of evolution even before the publication of Darwin's Origin of Species. He carries the idea through the whole range of philosophy in his great System of Synthetic Philosophy and undertakes to show that development is the highest law of all nature, not merely of the organic. As the foundation of all that exists, though itself unknowable and only revealing itself in material and mental forms, he places a power, the Absolute, of which we have but an indefinite conception. The individual processes of the world of phenomena are classed under the head of evolution, or extension of movement, with which integration of matter, union into a single whole, is connected, and dissolution or absorption of movement, which includes disintegration of matter, the breaking of connection. Both processes go on simultaneously, and include the history of every existence which we can perceive. In the course of their development the organisms incorporate matter with themselves; the plant grows by taking into itself elements which have previously existed in the form of gases, and the animal by assimilating elements found in plants and in other animals. The same sort of integration is observed in social organisms, as when nomadic families unite into a tribe, or subjects under a prince, and princes under a king. In like manner integration is evident in the development of language, of art, and of science, especially philosophy. But as the individuals unite into a whole, a strongly marked differentiation goes on at the same time, as in the distinction between the surface and the interior of the earth, or between various climates. Natural selection is not considered necessary to account for varying species, but gradual conditions of life create them. The aim of the development is to show a condition of perfect balance in the whole; when this is attained, the development, in virtue of the continuous operation of external powers, passes into dissolution. Those epochs of development and of dissolution follow alternately upon each other. This view of Spencer suggests the hodos and and hodos kato of Heraclitus, and his flowing back of individual things into the primal principle.
Similar principles are carried out not only for organic phenomena but also for mental and social; and on the basis of the theory of evolution a remarkable combination of intuitionism and empiricism is achieved. In his principles of sociology Spencer lays down the laws of hyperorganic evolution, and gives the various stages of human customs and especially of religious ideas, deducing all religion much too one-sidedly from ancestor-worship. The belief in an immortal " second self " is explained by such phenomena as shadows and echoes.