The two systems of philosophy which were dominant at the turn of the century were unfriendly to theistic and Christian belief. Naturalism on the one hand and Absolutism on the other could find no place for a positive faith in God, freedom and immortality. The opening years of the century witnessed a revolt against these two systems; and the leading characteristic of twentieth century thought, over against an agnostic naturalism and a pantheistic or impersonal absolutism, has been its reaffirmation of spiritual values. There has been a new emphasis upon the rights of personality, as against the enmeshing and enchaining forces of nature on the one hand and an all-engulfing Absolute on the other. Philosophical readers will remember the moral tonic of James' collection of essays, "The Will to Believe" (1902), with its picturesque style, its originality of standpoint and its moral enthusiasm. Here was a philosopher of medical training and of unquestioned scientific standing, and yet with the insight and earnestness of a prophet, making a valiant defense of spiritual realities, of human freedom, and the rights of the volitional and moral sides of our nature. As an evolutionist he contended that "the strenuous type of character will on the battle-field of human history always outwear the easy-going type, and religion will drive irreligion to the wall."[149] And as a psychologist he found that theism appealed to every energy of our active nature and released the springs of every emotion, and held that "infra-theistic conceptions, materialism and agnosticism, are irrational because they are inadequate stimuli to man's practical nature."[150] 149: "The Will to Believe," p. 213. 150: _Ibid._, p. 134. Readers who had been breathing the stifling air of naturalism, so fatal to spiritual aspiration, or the too rarified atmosphere of absolutism with its "transcendence" of personality and moral distinctions, will remember also the sense of satisfaction and relief with which they read that other volume of protest, from the other side of the water, "Personal Idealism" (1902). It was refreshing to find that there was a body of brilliant young thinkers, alive to the scientific atmosphere of the time, and trained in the philosophic orthodoxy of the English schools, and yet boldly asserting the rights of personality in God and man.