Behind the superficial obscurity of what fragments we have of Heraclitus' thought, Professor Kahn claims that it is possible to detect a systematic view of human existence, a theory of language which sees ambiguity as a device for the expression of multiple meaning, and a vision of human life and death within the larger order of nature. The fragments are presented here in a readable order; translation and commentary aim to make accessible the power and originality of a systematic thinker and the first great master of artistic prose. The commentary locates Heraclitus within the tradition of early Greek thought, but stresses the importance of his ideas for contemporary theories of language, literature and philosophy.