We are born with what may be roughly described as a vaguely differentiated mass of mental tendency, vast and potent, but unformed and needing direction—_informe, ingens, cui lumen ademptum_. This instinctive material is believed to be the outcome of age-long social development in the race, and hence to be, in a general way, expressive of that development and functional in its continuance. The process of evolution has established a probability that a man will find himself at home in the world into which he comes, and prepared to share in its activities. Besides the tendency to various sorts of emotion, we have the thinking instinct, the intelligence, which seems to be fairly distinct from emotion and whose function includes the co-ordination and organization of other instinctive material with reference to the situations which life offers. At any particular stage of individual existence, these elements, together with the suggestions from the world without, are found more or less perfectly organized into a living, growing whole, a person, a man. Obscurely locked within him, inscrutable to himself as to others, is the soul of the whole past, his portion of the energy, the passion, the tendency, of human life. Its existence creates a vague need to live, to feel, to act; but he cannot fulfil this need, at least not in a normal way, without incitement from outside to loosen and direct his instinctive aptitude. There is explosive material stored up in him, but it cannot go off unless the right spark reaches it, and that spark is usually some sort of a personal suggestion, some living trait that sets life free and turns restlessness into power. It must be evident that we can look for no cut-and-dried theory of this life-imparting force, no algebraic formula for leadership. We know but little of the depths of human tendency; and those who know most are possibly the poets, whose knowledge is little available for precise uses. Moreover, the problem varies incalculably with sex, age, race, inherited idiosyncrasy, and previous personal development. The general notions of evolution, however, lead us to expect that what awakens life and so gives ascendency will be something important or functional in the past life of the race, something appealing to instincts which have survived because they had a part to perform; and this, generally speaking, appears to be the case.