Diogenes Laertius

Diogenes Laertius is generally placed in the third century AD from evidence within his work. His own birthplace, career and exact life dates are not securely known. The name “Laertius” does not supply a certain hometown. Rather than filling these gaps with a story about travel or teaching, we can begin with the surviving author and his Greek text. He belongs to the Greek-speaking literary world under Roman rule, many centuries after several philosophers whose lives he records.

Above all, he must be distinguished from Diogenes of Sinope, the fourth-century BC Cynic famous for provocative anecdotes. That earlier Diogenes is a subject in Book VI, not the author of the collection. Laertius gathers biographies, opinions, book lists, sayings and documents from earlier traditions, many now lost. He names authorities, but naming one does not always mean that he consulted the original directly. His collection also includes poems of his own. Such features make him a visible arranger of material, rather than an invisible window onto the past. The uncertain biography should direct attention toward his methods of selection and transmission, not invite invented personal details.

The surviving Lives of Eminent Philosophers consists of ten books. The four entries below are parts of that single collection, ordered by book number; they are not four independent publications with known release dates. Book I introduces origins and early sages, Book II includes Socrates, Book VI the Cynics, and Book X Epicurus. Its organization follows philosophical successions as well as individual lives, rather than a simple modern timeline.

The quotation comes from the narrator's own introduction, where he proposes two beginnings or lines of philosophy, associated with Anaximander and Pythagoras. It is his organizing scheme, not a universally accepted account of every philosophical tradition. Elsewhere the text shifts between narration and quoted documents. Book X is especially valuable because it preserves three letters of Epicurus and the Principal Doctrines. These embedded texts retain their own attributed author: they do not become statements by Laertius merely because he transmits them. Conversely, an entertaining anecdote is not automatically a verified event. Reading the collection therefore involves following both a philosophical story and the signs that identify a source, a competing account or a change of voice. Its historical importance includes preservation, while each individual report still requires examination.

Make a small Greek source card for one passage. Write the name of the philosopher, the reporting writer, and the book and section number: “Diogenes Laertius, VII.23” points to Book VII, section 23. Summarize in Modern Greek with αναφέρει ότι or παραθέτει τα λόγια, and underline where another speaker's words begin. Then compare βίος and βιογραφία with the everyday ζωή. This activity practises reporting verbs, reference numbers and the difference between author and subject. Finally place two sentences side by side: one stating what the text says, the other what the evidence allows you to conclude. A useful Greek summary keeps those two tasks visible.

• He is the biographer, not Diogenes the Cynic.
• His collection has ten books.
• Book X preserves three letters attributed to Epicurus.
• His exact life dates and hometown remain uncertain.