A systematic study of rational or justified belief, which throws fresh light on current debates about foundations and coherence theories of knowledge, the validation of induction and moral scepticism. Dr Nathan focuses attention on the largely unsatisfiable desires for active and self-conscious assurance of truth liable to be engendered by philosophical reflection about total belief-systems and the sources of knowledge. He extracts a kernel of truth from the doctrine that a regress of justification is both necessary and impossible, contrasts the resultant scepticism with more familiar complaints about the inapplicability of supposedly essential cognitive concepts and explores the feasibility of non-Humean modes of consolation. This is an original and carefully constructed book, which will interest professional philosophers and advanced students of epistemology.