The opinion of Professor Loria is summed up as follows: the thesis that the Darwinian theory is entirely applicable to political economy is false. It is said that it justifies social inequality; nature being aristocratic, in society also the aristocracy occupies the place that belongs to it. According to Professor Loria this argument is as without sense as the argument that, since nature is a murderess, murder is justifiable. The view in question is not a legitimate conclusion from the theory as advanced by Darwin, but is simply a false interpretation made by some of his followers. There are no reasons why this struggle should always exist, but we are quite justified in supposing that it will disappear, having been but a transitory stage. For as long as egoism was the sole human motive, the struggle for existence was a necessary condition of initiative and progress. But altruism is more and more developing, and it is not Utopian to believe that some day man will reach out after physical and moral perfection, not with the aim of conquering his less-favored fellows, but with the higher aim of self-development. We forget too much how different is the struggle for existence among animals and among men. While in nature it is the strongest, hardiest, and most skilful who come out of the contest victorious, and consequently survive, in the present contest it is not the best (the workers and the capitalists who introduce improved methods of work), but those who are enriched by the labor of others, who are the conquerors. In the social struggle we perceive three phenomena which do not appear in the struggle in nature: military selection (which is an obstacle to the perfection of the human race); sexual selection (in which not strength and beauty, but money and class-prejudice determine the choice); and the economic system (which by the accumulation of capital in the hands of a few, forces the workers to lead a life that exhausts them, and is the reason why the ill-nourished classes form the majority). This is why the results of the struggle for existence are so different for man from those of the combat in nature. Professor Ferri makes the following objections to what has been said above: In treating questions like these it is necessary not to confuse two theories, that of Spencer and that of Darwin. For the latter is connected with the former as a part with the whole. Darwinism is expressed in the law of natural selection, while the theory of Spencer is that of evolution, a law which rules not only the animal and human world, but also the whole knowable universe.