The Meno, by Plato.
Meno (Ancient Greek: Μ?νων) is a Socratic dialogue written by Plato. It attempts to determine the definition of virtue, or arete, meaning virtue in general, rather than particular virtues, such as justice or temperance. The first part of the work is written in the Socratic dialectical style and Meno is reduced to confusion or aporia. In response to Meno’s paradox (a.k.a. the learner’s paradox), however, Socrates introduces positive ideas: the immortality of the soul, the theory of knowledge as recollection (anamnesis), which Socrates demonstrates by posing a mathematical puzzle to one of Meno’s slaves, the method of hypothesis, and, in the final lines, the distinction between knowledge and true belief.