Plato

Plato was an ancient Greek writer and philosopher and was the student of another known philosopher, Socrates.

William Blake recalled that Plato had argued that the nature of reality was unknown and that one's perceptions were like shadows cast on the wall of a cave. (PROSE: The Pit)

The Doctor's companion Vicki had never heard of either Plato or Socrates. (PROSE: Byzantium!)

The Fourth Doctor and Leela met Plato at a gathering at Anaximander's home. (PROSE: The Brain of Socrates)

The Library of St John the Beheaded contained some of his lost works. (PROSE: All-Consuming Fire)

Bernice Summerfield met Plato and his teacher Socrates whilst time-travelling. (AUDIO: The Oracle of Delphi)

The Eleventh Doctor, Amy Pond and Rory Williams also met him and his mentor. (COMIC: The Chains of Olympus)