An Athenian citizen from an influential aristocratic family, Plato is believed to have lived between approximately 429 and 347 BCE. Stories about his life were told in later ancient sources, but biographical details are disputed and tend not to be taken at face value. Plato is known for composing his philosophical texts as dialogues, featuring a small group of interlocutors, typically historical figures, conversing or debating a topic, almost always with Socrates present.

Plato’s work has been characterized into early, middle, and late periods. Of the texts in The Last Days of Socrates, Euthyphro, the Apology, and Crito are said to belong to Plato’s early period and Phaedo to the middle. Arguably his most famous work is the Republic, a late period work which sets out to describe the ideal city and person.

The foundational contrast at the heart of Plato’s philosophy is that the ideal cannot be accessed by the body; there is a gap between what can be observed and known through the body’s senses and the essence of a thing. The divide between body and soul exemplifies this contrast, as the body is the mutable, destructible part of the human and the soul the immutable, eternal part. The philosopher is one who acknowledges and explores this distinction to understand what is good, wise, and just.