The artificial nature of the abstraction which distinguishes the scientific from the moral and the religious consciousness, as well as the impossibility of simultaneously exercising faith and repressing it, is plainly exhibited in the optimistic interpretation of evolution. The premises from which it starts are faith in the uniformity of Nature and belief in the reality of material things. The conclusions which it reaches constitute a _non sequitur_ if they are supposed to follow from the avowed premises, and only command assent when we tacitly assume certain moral and religious presuppositions which, if not avowed in the optimist's argument, are instinctively supplied by the moral and religious consciousness of the optimist's disciples. That the process of evolution on the whole has been and will be a process of progress follows logically enough from the optimist's avowed premises, if by progress we mean the survival of those best fitted to survive--that is, if we empty the notion of progress of all moral meaning. But as the conclusion that evolution is progress is the conclusion which is necessary for the justification of the common faith of mankind, the illogical nature of the optimist's process of inference is apt to be overlooked in consideration of the satisfactory termination of his argument. It is, however, necessary, in the interests of clearness of thought as well as of the moral and religious consciousness, that the conception of progress thus thoughtlessly emptied of meaning by the optimist should have its context restored. This service--a service essential as a preliminary to every theory of evolution--was rendered by one in whom the moral consciousness spoke with force--Professor Huxley. To him is due the demonstration that adaptation to environment, so far from being the cause of progress, counteracts it; so far from being man's ideal, it is that which resists the realisation of his ideals. Progress is effected, according to Professor Huxley, not by adaptation to but adaptation of the environment, and consists in approximating to the ideals of art and morality--which ideals are not accounted for, as ideals, by the fact that they are the outcome of evolution, because evil has been evolved as well as good. Why approximation to the ideal of religion--love of God as well as of one's neighbour--should not contribute to progress does not appear. If, however, we add it, and also add the ideal of science, viz. truth, then progress will be the continuous approximation to the ideals of truth, beauty, goodness, and holiness; and human evolution, so far as evolution is progress, will be the progressive revelation of the ideal in and to man.