Lives and Opinions of Eminent Philosophers

The Lives and Opinions of Eminent Philosophers is a biographical work by Diogenes Laërtius, a Greek author who lived in the 3rd century CE. This text is a crucial secondary source for understanding ancient Greek philosophy, offering insights into the lives, teachings, and sayings of numerous philosophers.1

The work is a compilation that includes gossip, valuable biographical details, summaries of doctrines, and even reproductions of documents like wills. Diogenes Laërtius organized his material into an Ionian branch and an Italic branch of philosophy, detailing various schools and individual thinkers within them. While he cited many authorities, his knowledge was often secondhand, and his primary sources are not always clear. The surviving manuscripts date back to the 12th century, with parts of Book VII missing. The work provides a broad overview of philosophical thought, making it an important resource for scholars of ancient philosophy.1