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was made a matter of general attention by the publication of Darwin's “ Origin of Species," in 1859. Within the limits of a generation, the evolutionary hypothesis gained the acceptance of most scientists, though not always in the Darwinian form, with its special stress upon the instrumentality of “ natural selection," or the principle of “the survival of the fittest.”
If we ask how far the actual proof in favor of evolution extends, we find that it fairly establishes the fact of mutation of species within certain limits. As for the descent of all species from a common type, the evidence affords at most suggestion, not decisive proof. Science has no real insight into the capability of the processes which have effected ascertained variations of species to produce such vast changes as are implied in the transition from one kingdom or sub-kingdom of living forms to another. It is the advantage of a unified and connected view of the whole circle of the organic world, rather than any complete proof, which commends the theory of evolution, in its broad sense, to the scientist.
As respects its religious bearing, the doctrine of evolution is not necessarily held in the interest of sheer naturalism, or in opposition to genuine theism. This is well illustrated in recent remarks of one of the stanchest advocates of the Darwinian theory in its main elements. “There are at least three stages," he says, " in the development of the organic world, when some new cause or power must necessarily have come into action. The first stage is the change from inorganic to organic, when the earliest vegetable cell, or the living protoplasm out of which it arose, first appeared. This is often imputed to mere increase of complexity of chemical compounds; but increase of complexity, with consequent instability, even if we admit that it may have produced protoplasm as a chemical compound, could certainly not have produced living protoplasm, protoplasm which has the power of growth and reproduction, and of that continuous process of development which has resulted in the marvellous variety and complex organization of the whole vegetable kingdom. There is in all this something quite beyond and apart from chemical changes, however complex.
“The next stage is still more marvellous, still more completely beyond all possilibity of explanation by matter, its laws and forces. It is the introduction of sensation or consciousness, constituting the fundamental distinction between the animal and vegetable kingdoms. Here all idea of mere complication of structure producing the result is out of the question. We feel it to be altogether preposterous to assume that, at a certain stage of complexity of atomic constitution, and as a necessary result of that complexity alone, an ego should start into existence, a thing that feels, that is conscious of its own existence. Here we have the certainty that something new has arisen, a being whose nascent consciousness has gone on increasing in power and definiteness till it has culminated in the higher animals. No verbal explanation or attempt at explanation - such as the statement that life is the result of the molecular forces of the protoplasm, or that the whole existing organic universe, from the amba up to man, was latent in the fire-mist from which the solar system was developed - can afford any mental satisfaction, or help us in any way to a solution of the mystery.
“ The third stage is the existence in man of a number of his most characteristic and noblest faculties, those which raise him furthest above the brutes, and open up possibilities of almost indefinite advancement. These faculties could not possibly have been developed by the same laws which have determined the progressive development of the organic world in general, and also of man's physical organism.
“ These three distinct stages of progress from the inorganic world of matter and motion up to man point clearly to an unseen universe, — to a world of spirit, to
а which the world of matter is altogether subordinate. To this spiritual world we may refer the marvellously complex forces which we know as gravitation, cohesion, chemical force, radiant force, and electricity, without which the material universe could not exist for a moment in its present form, and perhaps not at all, since without these forces, and perhaps others which may be termed atomic, it is doubtful whether matter itself could have any existence. And still more surely can we refer to it those progressive manifestations of life in the vegetable, the animal, and man, which we may classify as unconscious, conscious, and intellectual life, and which probably depend upon different degrees of influx.” 1
Evolutionism of a realistic type, such as is expressed in Darwinism and cognate theories, had been preceded by an idealistic evolutionism. Of this latter the Hegelian system was the most elaborate specimen. In the recent philosophy of Britain, the former type may have been the most conspicuous factor, but the Hegelian speculation has also left an impress. Before the impact of either had produced any definite results, a phase of philosophy which rests back upon Hume and Locke had its school in England. It will be necessary, therefore, in tracing the philosophical current, to go back of its juncture with the theory of evolution.
1 A. R. Wallace, Darwinism, 1889, pp. 474-476.
The school to which we refer was represented by James Mill and his son, John Stuart Mill, the latter being its most fertile writer. In its underlying postulates it savored of extreme empiricism and sensationalism. It made no account of an original content or source of ideas in the mind, derived all intellectual products from sensation, explained necessary beliefs by the power of association, and discredited at once the substantiality of mind and its freedom, thus making it a necessitated chain of sensations.
In the hands of John Stuart Mill this scheme scarcely came short of confessed failure. “If we speak of the mind,” he says, “ as a series of feelings, we are obliged to complete the statement by calling it a series of feelings which is aware of itself as past and future; and we are reduced to the alternative of believing that the mind, or ego, is something different from any series of feelings, or possibilities of them, or of accepting the parodox that something which ex hypothesi is but a series of feelings can be aware of itself as a series." 1 In view of this insurmountable difficulty, it would have been creditable in Mill to have abandoned his definition of mind, and thus to have changed the base of his philosophy. He might also have found adequate occasion for amendment of his system in the fact that he could not see his way clear to maintain his denial of innate principles or fixed
1 Examination of Sir William Hamilton's Philosophy.
data of thought, except as he questioned at the same time the certainty of even mathematical truths, and thus cut away the ground for all scientific confidence.
With the sensational philosophy a utilitarian theory of morals has commonly been conjoined. Jeremy Bentham, who began his career as an author in the last quarter of the eighteenth century, was a stalwart advocate of this theory. “ Nature has placed mankind,” he says, “ under the governance of two sovereign masters, pain and pleasure. It is for them to point out what we ought to do, as well as to determine what we shall do. On the one hand, the standard of right and wrong, on the other the chain of causes and effects are fastened to their throne. They govern us in all we do, in all we say, in all we think." 1 Following in the path traced by Bentham, James Mill and John Stuart Mill have contended for the utilitarian, or hedonist, theory. The latter says, in exposition of the theory: “ The creed which accepts, as the foundation of morals, utility, or the greatest happiness principle, holds that actions are right in proportion as they tend to promote happiness, wrong as they tend to produce the reverse of happiness.”? He remarks further: “To think of an object as desirable and to think of it as pleasant are one and the same thing; and to desire anything, except in proportion as the idea of it is pleasant, is a physical and metaphysical impossibility. ... Will in the beginning is entirely produced by desire, including in that term the repelling influence of pain, as well as the attractive one of pleasure. . . . Will is the child of desire, and
1 Introduction to the Principles of Morals and Legislation, p. 1. 2 Utilitarianism.