_Ceteris paribus_, an increase of individual energy is an advantage to society; and, as a matter of fact, we find that civilized society differs conspicuously from the ruder in stimulating more vigorously and systematically the various energies of its members. The most conspicuous virtue of this class is the virtue of courage. In more primitive conditions, courage, as necessary to the preservation of society, is regarded as a virtue in itself; later, some mixture of judgment and reason is required in its exercise; and finally, since it may be combined with other anti-social qualities, it is not approved in the same manner as the more directly social virtues. Courage is now regarded merely as one manifestation of a character which is fitted for all the requirements of social existence. The courage of the bulldog is blind instinct. Where such an instinct exists, the animal survives by reason of it, not because he forms any conscious judgment of its advantages. It seems necessary to suppose that races owed their survival to military prowess when reflection was still in the most rudimentary stage. The utility of courage must have been a very obvious discovery as soon as reflection became possible; but the quality must have existed, in some degree, before it could be discovered, although the existence of a distinct moral sentiment doubtless implies some reflection. Moreover, the instincts which imply a perception of utility must themselves comply with the conditions of existence, must themselves be useful. Increased intelligence might act to the disadvantage of the race by increasing selfish cowardice through a keener perception of personal, as distinct from social, risk; but this cannot be true ultimately, since we perceive that intelligent races have an advantage; we may suppose that those races are most successful in which a perception of the vitality of courage goes along with an increase of courage. This principle must be regarded, therefore, as working, not only through the less conscious instinct of the lower races, but also upon the judgments of a highly civilized society. The like is true, _mutatis mutandis_, of other qualities (such as industry, energy, and so forth) which belong to the same class.