The naturalism of Theodore Dreiser may be approached through a study of his personality, the sort of experiences he had in his formative years, and the philosophical speculations which grew from his experiences and his reading. A warm, boundless human sympathy; a tremendous vital lust for life with a conviction that man is the end and measure of all things in a world which is nevertheless without purpose or standards; moral, ethical, and religious agnosticism; contact with the scientific thought of the late nineteenth century which emphasized the power and scope of mechanical laws over human desires; belief in a chemical-mechanistic explanation of the human machine—an explanation which substantiates his materialism while it does full justice to the mystery of consciousness and the vital urge;—these are the elements which Dreiser brings to the Creation of his novels. It must be emphasized that his awareness of the shifting, cyclical quality of human and natural affairs arises as much from experience as from his contact with literary models or scientific thought. His determinism, again, loses its force because he is more interested in the mystery and terror and wonder of life itself than in tracing those forces which might account for and so dispel the mystery. Science is not, to him, the wonderful high priest of benign Nature, because he has seen too many of the evils of industrialism and the malignancy of natural forces. But life is eternally seeking, searching, striving, throbbing—life is the single positive element in a cosmos of ruthless flux. And the pathetic fortunes of people in this cosmos of purposeless change are the main concern of Dreiser's novels.