Diogenes Laertius

Diogenes Laërtius was a biographer of the Greek philosophers. Little is definitively known about his life, but his surviving work, Lives and Opinions of Eminent Philosophers, remains a primary source for the history of ancient Greek philosophy. His reputation is controversial among scholars because he often repeats information from his sources without critically evaluating it. In many cases, he focuses on insignificant details of his subjects' lives while ignoring important details of their philosophical teachings and he sometimes fails to distinguish between earlier and later teachings of specific philosophical schools. However, unlike many other ancient secondary sources, Diogenes Laërtius tends to report philosophical teachings without trying to reinterpret or expand on them, and so his accounts are often closer to the primary sources. Due to the loss of so many of the primary sources on which Diogenes relied, his work has become the foremost surviving source on the history of Greek philosophy.

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