Heraclitus

Heraclitus (fl. c. 500 bc), Greek philosopher, who believed that fire was the primordial source of matter and that the entire world was in a constant state of change. He was born in Ephesus, an ancient Greek city in Asia Minor, in what is now Turkey. Because of the loneliness of his life and the obscurity and misanthropy of his philosophy, he is sometimes called the dark philosopher or weeping philosopher.

Heraclitus was, in a sense, one of the founders of Greek metaphysics, although his ideas stem from those of the Ionian school of Greek philosophy. He postulated fire as the primal substance or principle that, through condensation and rarefaction, creates the phenomena of the sensible world. Heraclitus added to the “being” of his predecessors the concept of “becoming”, or flux, which he took to be a basic reality underlying all things, even the most apparently stable. To illustrate this he stated that a person could not step into the same river twice.

In ethics Heraclitus introduced a new social emphasis, holding virtue to consist in a subordination of the individual to the laws of a universal, reasonable harmony. Although his thinking was strongly influenced by popular theology, he attacked the concepts and ceremonies of the popular religion of his day.

Only one work, On Nature, is definitely attributable to Heraclitus. Numerous fragments of this work were preserved by later writers, and collected editions of these surviving fragments may be found in several modern editions.