The Lives and Opinions of Eminent Philosophers

Lives and Opinions of Eminent Philosophers is a historical-biographical work by Diogenes Laërtius, written around the 3rd century CE. It is one of the most important surviving sources on the lives and teachings of ancient Greek philosophers. The work is organized into ten books and presents biographies, sayings, anecdotes, and doctrines of major Greek philosophical schools. It covers figures from early pre-Socratic thinkers up through Plato, Aristotle, and the later Hellenistic schools such as the Stoics, Epicureans, and Cynics. Rather than being a strictly analytical philosophical text, it is more of a compilation of stories and traditions. Diogenes Laërtius includes both serious philosophical summaries and colorful anecdotes—some reliable, others clearly legendary or humorous. A well-known feature of the work is its inclusion of memorable sayings and lifestyle descriptions. For example, it preserves many anecdotes about Socrates, Plato, and especially the Cynic philosopher Diogenes of Sinope, who is portrayed in vivid and sometimes exaggerated stories.