Now, unfortunately, this selection is carried out only on certain lines, and it does not follow that this upper class will invoke our entire sympathy and approbation. In biological works we frequently hear of the “survival of the fittest,” and the expression is used by biologists in quite a special and technical sense. It does not mean of necessity that the most active or intelligent always survive; indeed, this is far from being a rule of universal application. Often the most fit are inactive and mentally inert, as when the tame duck with useless wings and the mole with useless eyes is preserved while others die off. In these cases the wings and eyes are useless, and, although the animals looked at by themselves would appear to have become less excellent, yet in view of their surroundings they have a better chance than would be the case were their endowments of a higher order. Biologists use then the term “fit,” simply in the sense of “fit to get on in the world,” and often intrinsically inferior animals and men are “fit” in this sense of the term. Now, those who are to form this upper class, or classes, of which we have been speaking, will be fit in the technical meaning of the word, for they will have been able best to conform to the conditions necessary for their advancement laid down by society at large. Whether or not these fit will form an aristocracy of high merit will depend upon the kind of conditions with which they have to comply, in fact it will depend upon the selection that society makes.