The fact of the existence of altruistic feelings in the texture of the Ego has led to the theory that all altruistic actions, since they arise out of the constitution of the Ego, are really egoistic. This argument is irresistible. A kind, sympathetic man or woman is so by virtue of innate qualities, just as the selfish or the brutal man is. And if the justification of actions were to depend upon the authority of natural egoism the one is as much capable of justification as the other. If Ethics depends for its explanation and justification upon Biology, then, since the view of Biology is limited to the individual and means the suitable adjustment of every moving equilibrium to its special environment, each is capable of equal justification and similar explanation. Egoism may include Altruism or it may not, but in either case the action is equally valid from the point of view of Biology. If, however, an extension of this view be argued for on the theory that a rationalistic view of all the requirements of the subjective surroundings involves a certain line of conduct in order to secure a suitable adaptation between the organism and the environment, which shall be the equation of that organism, the best adaptation for the time being--this will be a superior, because a more extended, biological aspect of conduct, and it is not disputed that such a view of life may be more or less acted upon. But neither the Ego-altruistic view, nor the prudential rationalistic view attains to the true ethical point of view of human conduct; for the altruistic growth in the Ego is not universal, nor of equal development; and the prudential rationalistic motive is purely egoistic and biological, and therefore adverse to the altruistic, even if it exists in the Ego. The main object of the present argument is to shew that the purely biological explanation of ethical injunctions is insufficient as a means of understanding their imperative character. And yet it is difficult to say this if Biology is to be considered as the law of actions of organisms. It all depends upon the factors which are included in the generalisation. If the factors are simply physical, then the generalisation is insufficient; if the forces included in the moving equilibrium include subjective forces capable of growth into sympathy or Altruism, then the biological laws receive, perhaps, an extension which renders them capable of determining the whole of the phenomena. But if Pleasure and Pain are limited to life-sustaining acts or life-destructive acts, then the influence of the subjective factors is limited to the physical, and the super-growth of correspondences of inner with outer (which is necessary to explain the larger growth of feeling) transgresses the narrow limits of the biological law--the law of simple equilibration between the organism and its environment.