In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Theophrastus wrote that this author's one completed work was a papyrus he left in the Temple of Artemis which criticized Anaximander for underestimating the role of injustice in men's lives. Diogenes Laertius wrote that his works were left unfinished because of melancholia, which caused him to be referred to as the "the weeping philosopher. " His is known for arguing that "everything is in a state of flux," and he established a term for the fundamental order of the cosmos: Logos. For 10 points, name this pre-Socratic thinker who thought all matter was made of fire and said something about not being able to step into the same river twice.
Social Science