Plato is a well-known, intellectual Athenian philosopher that was born into an aristocratic family. Due to his family's wealth, Plato was able to receive some of best education available to Athenians. When Plato was a pupil, he became infatuated with his Sophist Socrates. Socrates was a Greek philosopher and he was known to preach endlessly about his ideas and theories to anyone that would listen. Plato's most renowned work comes from his Five Dialogues. In two of Plato's dialogues, Meno and Phaedo, Socrates is the protagonist and Plato uses his character to portray his philosophical views of life and how one can go about acquiring knowledge.
The Meno consists of a discussion between Socrates and his companion, Meno, in which Meno is trying to inquire information on whether "virtue can be taught? Or is it not teachable but the result of practice, or is it neither of these, but men possess it by nature or in some other way" (70a). In the beginning of the dialogue, Socrates asks Meno to define what virtue is and after numerous attempts, Socrates comes to realize that he himself is unclear on whether or not virtue can be taught so he suggests that they can seek out the answer together. Meno is puzzled because he doesn't know how the two of them will search and acquire knowledge on virtue if they are both unfamiliar with the subject. Socrates' responds with a debate he once heard from some priests and priestesses about how "the human soul is immortal; at times it comes to an end, which they call dying; at times it is reborn, but it is never destroyed, and one must therefore live one's life as piously as possible" (81b). Socrates informs Meno that knowledge is derived from the immortality of the human soul, not via learning, and "it is in no way surprising that it can recollect the things it knew before, both about virtue and other things" (81d). Socrates is saying that if one wants to acquire knowledge about a particular subject, then they will have to search within their soul to recollect the information stored in there from previous lives.
Meno then asks Socrates if he can somehow teach him how one acquires their past knowledge through their soul. Socrates agrees and he is going to demonstrate his theory of recollection on one of Meno's slave. Socrates method entails him asking Meno's slave a question about geometry, a topic the slave is unfamiliar with, in which he will challenge the slave to recollect knowledge, via his soul, that he learned in a previous life. At first, the slave is unable to answer Socrates' questions, but eventually, after he recollects knowledge from his soul, the slave is able to give Socrates the correct answer. Socrates then asks Meno "Must he not either have at some time acquired the knowledge he now posses, or else have always possessed