The main fact underlying all Ethics is the existence of a society composed of subjective factors, factors possessing feelings and reasoning powers. The fundamental notion in Ethics is the regulation of the mutual conduct of these factors. It is the voice of the million against the voice of the unit which decides the duty of the unit. It is the voice of the individual against the voice of society claiming a modification of opinion. It is the voice of individuals to other individuals specifying general duty. Broadly speaking it is the claim of duties towards other individuals upon the Ego. But it follows from the universality of the claim, that there is mutuality of claim, and the duties which are demanded have at the same time to be acknowledged. The principle can be easily accepted as theoretically correct, and many general rights and duties can be readily deduced as corollaries, but beyond these general rules ethical problems have rather to be worked out than thought out--in the more important matters by societies during their upward growth, in smaller matters by individuals through multitudinous adjustments and re-adjustments. I do this or that in contravention of some accepted social law. I am condemned, and am made so generally uncomfortable by the social penalties that I am coerced into conformity, or, otherwise, society modifies its opinion in acknowledgment of my right to do as I have done. But then the question arises, upon what principle should ethical judgments be formed? Since society demands the performance of certain actions, while it prohibits the performance of others, and since its aim is the biological completeness of each of the individuals, what are the principles upon which it determines the restraints and imposes the injunctions so as not to interfere too much with individual liberties? This principle finds very good expression in Mr. Spencer's formula. The whole problem comes before us when we have to consider the relative claims of egoism and altruism, a problem splendidly worked out by Mr. Spencer, in the chapters entitled "Egoism _versus_ Altruism," "Altruism _versus_ Egoism," "Trial and Compromise," and "Conciliation." As this is a purely critical work, to be read only in conjunction with the work criticised, we do not feel called upon to give an account of these chapters. We simply state our acceptance of them bodily, the reservations we would make being merely in regard to certain details of the exposition. We ought to reprint them here in order to make this work complete in its argument, but it is simpler to ask the student to interrupt his reading of this criticism by a reperusal of the chapters referred to. * * * * * *