5. David Hume (1711-1776) brought the critical analysis of the process of human knowledge to a provisional conclusion, especially through his investigation of the two concepts which had played such an important part in the seventeenth-century systems of thought, the concepts of substance and causality. In order to understand the significance of his criticism we must remember that the concepts just named are the presuppositions which are tacitly understood as forming the basis of natural science, of religious thought, and of ordinary conversation. Hume's problem strikes at the root of all human thought. He stated a problem which still continues to bid for solution and of which a final solution is perhaps impossible. Hume is a past master in stating problems. With this he likewise combines a profound psychological talent which enables him, when considering the actual evolution of ideas, to throw light on those points also in which their objective validity remains problematical. This twofold gift is valuable to Hume both in the investigation of the problem of knowledge, as well as in the investigation of the problems of ethics and religion.
Hume was the son of a landlord in southern Scotland. His zeal and aptness for learning and reflection showed themselves at an early age. After several vain attempts to enter some practical vocation he withdrew into retirement and wrote his chief work, the Treatise on Human Nature, during a residence in France (1739-1740). A little later he devoted himself to historical and economic investigations and wrote a history of England, one of the first historical works which takes account of every phase of cultural evolution. His Essays (1748 ff.), besides important treatises on economic subjects, include
