Properly to effect this object, it is necessary to study the influence of the emotions as determining conduct. Next, the influence of the reason as determining conduct, and finally, the interaction of the race and the individual (Ch. ii. and iii.). These preliminaries are succeeded by a study of the moral law as derived from social interests, following upon social necessities, establishing the moral law as natural, and as authoritative (Ch. iv.). The contents of the moral law are next discussed, in which the virtues of courage, temperance, truth, and the social virtues are considered (Ch. v.). Altruism, as a growth within the Ego, is necessarily an object of study, and is explained as a natural development of sympathy out of intrinsic subjectivity. Its place in a system of ethics is also set forth. (Ch. vi.). Upon this follows an exposition of special views upon merit, free-will, effort, and knowledge, as modified by the acceptance of the doctrine of evolution. Of essential importance to an ethical work is a consideration of the nature of conscience and the variations of its judgments (Ch. viii.). A discussion of happiness as a criterion succeeds, including a study of utilitarianism, and a consideration of the relations of morality and happiness (Ch. ix. and x.). A concluding chapter sums up a work of nearly 500 closely printed pages. It is very evident that we cannot undertake the criticism of so large and important a work without having to enter minutely upon points of agreement and difference which would greatly augment the size of our present volume. We need only say that, although there are naturally many minor criticisms to be made, we accept it as an excellent exposition of modern ethical views modified and co-ordinated as necessitated by the recognition of the Darwinian theories. It should be read, we think, in succession to Professor Sidgwick's excellent broad and dispassionate work on "The Methods of Ethics." Mr. Leslie Stephen's study is based upon the same scientific fundamentals as Mr. Spencer's "Data of Ethics," without the confusing cosmical views which are necessitated by Mr. Spencer's position, but which do not by any means tend to strengthen it. CHAPTER VII. THE EVOLUTION OF FREE WILL. Two distinct theories may be held by the Evolutionist with respect to volition, both of them being strictly causational, and, therefore, of a scientific, as opposed to a mystical character.