more important question than this is raised in the application of evolution to ethics. In strictness, the theory of evolution is simply an explanation of an order of sequent facts or processes. It is purely historical. We might know all that there is to be known about the origin and growth of moral institutions and ideas, and yet be unable to distinguish between good and evil or to set up a standard for right conduct. And this is the fundamental problem of ethics. The question which it has to answer is not a question of history at all, but of worth or goodness. In attempting to deal with this question, evolution has been pressed into alliance with the more general theory which is now known as Naturalism. In alliance with Naturalism it professes to be a complete philosophy, and has made a special claim to have revolutionized ethics and set that science on a new basis. It has been my purpose, accordingly, to examine this claim, and to discuss the ethical bearings of Naturalism, both in its earlier forms, before evolution came to its aid, and in its later and more impressive developments. The book is called a 'criticism'; but it is the criticism of a theory rather than of writers; and an effort has been made to overlook no aspect of the theory which may appear to have ethical significance."
Distinguishing the possible alternative solutions of the ethical problem as Realism or Naturalism and Idealism or Spiritualism, Mr. Sorley thus characterizes the former. "The theory now commonly called Naturalism may be said to occupy the position and to carry on the traditions of the theory of Materialism which, in its strict meaning, is no longer prominent in philosophical controversy. Naturalism, as the theory is held to-day, does not assert that material atoms and their motion constitute the sole reality. As regards ultimate reality it professes that it has nothing to say; it deals with phenomena only. But, in its interpretion both of the world and of man, it carries on the opposition to Idealism. The completest account of the world as a whole which is possible is held to be the description of it in physical terms; the spiritual factor in reality is held to be dependent, if not illusory. And the explanation given of man's life is similar. The psychology now associated with Naturalism is essentially the same as that which Democritus in the ancient world and Hobbes in the modern set forth as a suitable outwork of their materialistic theory of reality." And the one theory, like the other, is either individualistic or historical, the individualistic being the earlier, the historical the later and contemporary version of the theory. "On the basis of Naturalism, we may either look upon man as an individual distinct from other individuals, as was done by Epicurus
