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Plato

Ancient philosophy

Plato (424–347 BC) was a Greek philosopher from Athens. A disciple of Socrates, he wrote a series of dialogues in which Socrates appears. Later dialogues such as The Republic set out the celebrated Platonic doctrine of the Ideas, which distinguishes between two realities: the sensible world — that which we perceive — and the intelligible world, or world of Ideas. He was sold into slavery by Dionysius of Syracuse and later freed. He founded a school, the Academy, and Aristotle was among his disciples.

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Plato's Works Summarised on This Site

Symposium

At a banquet, Socrates and the other guests decide to take turns speaking in an attempt to define what Love is.

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Republic

In The Republic, Plato imagines the principles that would govern an ideal City. This is an opportunity for him to set out the famous Platonic doctrine of the Ideas.

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Bibliography

Here are the essential books if you want to better understand this author's thought:

Fine, Gail (1999), Plato 1: Metaphysics and Epistemology, Oxford University Press
Dorter, Kenneth (2006), The Transformation of Plato's Republic, Lexington Books
Kahn, Charles H. (1996), Plato and the Socratic Dialogue: The Philosophical Use of a Literary Form, Cambridge University Press
Fine, G. (ed.), The Oxford Handbook of Plato, Oxford University Press
Nails, Debra (2002), The People of Plato: A Prosopography of Plato and Other Socratics, Hackett Publishing

Recommended Videos

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Biography: Life of Plato

Youth

Plato was born in Athens in 428 BC, shortly after the death of Pericles, into a wealthy aristocratic family with connections to the oligarchic ruling class.

"Plato" may simply have been a nickname — derived from platos, meaning "breadth" — given to him on account of his broad shoulders. He is said to have been handsome and powerfully built, according to Epictetus, and reportedly competed as a wrestler at both the Olympic and Isthmian Games, winning two prizes.

According to Diogenes Laërtius, in his youth he was reserved and wise to the extent that he was never seen laughing out loud.

He first devoted himself to poetry — tragedies, lyrical verses and the like — and also took up painting and music. He was a pupil of Theodorus of Cyrene, who had also taught Socrates.

Learning Philosophy

Then, at twenty, he met Socrates and turned to philosophy. He burned all his writings and abandoned any thought of competing in the tragic contests.

He became Socrates' disciple for nine years, from 408 to 399 BC, until Socrates was condemned to death.

According to Diogenes Laërtius, it is said that Socrates had a dream: he saw on his lap a swan which covered itself with feathers and flew away. The next day, Plato came to join him as a disciple. And Socrates declared that Plato was the bird he had seen in his dream.

He began writing his dialogues, featuring Socrates, while the latter was still alive. After a public reading of one of his works, the Lysis, his master exclaimed: How many things this young man makes me say that I have never thought of!

Socrates

Socrates practised maieutics — the art of bringing forth ideas: rather than imposing his own views, he pressed his interlocutors with questions until an idea took shape in their own minds.

He was often ironic with his interlocutors, who believed themselves to know something — whereas Socrates, for his part, claimed to know nothing. Through his disconcerting questions, he exposed the emptiness of their supposed knowledge.

Socratic dialectic is the name given to this method of questioning in the service of the search for truth.

Plato's early dialogues are devoted to the search for essence, framed as questions of definition: "What is X?" In the Euthyphro, for instance: what is piety? In the Hippias Major: what is beauty?

He develops a sharp critique of the sophists, whom he reproaches for charging fees, for cultivating mere rhetoric rather than genuine wisdom, and for abandoning the pursuit of truth in favour of subjectivism — as expressed in Protagoras's formula: man is the measure of all things.

This period lasted nine years, after which Socrates was condemned to death by an Athenian court for "corrupting the youth". Philosophy had come to be viewed with suspicion — as a vehicle for spreading dangerous ideas through the city.

Plato, who was ill, did not witness Socrates' death. Fearing that he too might be arrested, he fled Athens with several other disciples and took refuge in Megara, a town a few dozen kilometres away.

The Theory of Ideas

He then came under the influence of Cratylus, a disciple of Heraclitus, and of Hermogenes, through whom he absorbed the wisdom of the Eleatics and in particular of Parmenides. It should be noted that, according to Aristotle, Plato had been a disciple of Cratylus before becoming a pupil of Socrates — though Diogenes Laërtius and other historians maintain the reverse.

These various influences fed his thinking. From Heraclitus, above all, he learnt that the sensible world — the world we perceive — is subject to perpetual change and that nothing in it endures (No man ever steps in the same river twice). He encountered the paradoxes of motion raised by the Eleatics, and Parmenides' concern with the question of being and non-being.

Here is how Diogenes Laërtius summarises these various philosophical influences: He made a synthesis of the theories of Pythagoras, Heraclitus and Socrates, taking from Heraclitus his theory of sensation, from Pythagoras his theory of intelligence, from Socrates his politics.

Plato then developed his own doctrine, grounded in a dualism between two realities, the sensible and the intelligible: the theory of Ideas.

The sensible world changes, decays and perishes. One must therefore posit a second reality — eternal and incorruptible — in which the Ideas or essences reside. A beautiful youth, for instance, grows old and dies; but the Idea of Beauty, in the intelligible world, remains eternal.

The supreme Idea is the Idea of the Good. We contemplated the Ideas in a previous existence and recover them through reminiscence.

Plato continues to use Socrates as the mouthpiece for his theory, even though the historical Socrates never held such views.

In 395 BC, back in Athens, he took part in the war against Corinth as a cavalryman — a campaign that ended in Athenian defeat by Sparta.

Travels

In 390 BC, he travelled to Egypt, where he is said to have met priests of the high clergy — though whether this journey actually took place is uncertain, since Plato's knowledge of Egypt appears indirect and limited.

He also travelled to southern Italy, to Taranto, where he encountered the Pythagoreans — Philolaus of Croton, Archytas of Tarentum and others. He discovered a doctrine that revealed to him a reality underlying the sensible world: the mathematical and permanent reality of number.

He then made his way to Sicily. Plato had distanced himself from political life early on, disillusioned by the excesses of the Thirty Tyrants and the condemnation of Socrates — not without regret, since in his view political engagement represented the highest expression of the philosophical life.

In Sicily he saw an opportunity to return to politics. He attempted, without success, to persuade Dionysius, the tyrant of Syracuse, to adopt reforms inspired by philosophy. He failed, and the two men fell out.

As Diogenes Laërtius relates, Plato discussed tyranny with him and constantly said that what was useful to a man was not truly good unless that man was virtuous. This offended Dionysius, who retorted, 'You speak to me like an old man!' 'And you talk like a tyrant,' replied Plato. Thereupon, more irritated than ever, the tyrant rushed to have him killed, but at the request of Dion and Aristomenes, he contented himself with handing him over to the Spartan Pollis, who was at the time on embassy in Sicily, to have him sold as a slave.

Reduced to the condition of a slave, Plato was ransomed and freed by Anniceris, a disciple of Socrates.

As Anniceris refused to be reimbursed, the ransom money was used to purchase a plot of land in Athens. A school was founded on it, and since the site lay close to the sanctuary of the hero Academos, it became known as the Academy.

The Academy

Plato taught for forty years in the school he had founded.

It attracted and trained distinguished pupils, among them Aristotle, Demosthenes, Theophrastus and Xenocrates.

The subjects covered included philosophy, naturally, but also mathematics and astronomy — two disciplines Plato held to be of paramount importance. Indeed, he had this phrase inscribed on the entrance to the Academy: Let no one enter here who is not a geometer.

Zoology and botany were perhaps also taught there.

It was the first philosophical school organised along the lines of a university in the modern sense: with rules, residential accommodation for students, a library and a lecture hall.

Oral teaching was considered paramount. Written transmission was accorded only limited importance.

In 366 BC, Aristotle entered the Academy at the age of seventeen and remained for twenty years.

According to Diogenes Laërtius, This Aristotle was the only one [...] to listen to Plato reading his treatise on the soul; all the other listeners left before the end.

The school endured for nine centuries, until the Byzantine Emperor Justinian brought it to an end in 529 AD.

Politics

After the death of Dionysius I, Dion — the tyrant's brother-in-law — offered to oversee the education of his successor, Dionysius II.

Plato had just completed The Republic in 372 BC, a work in which he reasserted the necessity of entrusting political power to the philosopher-king. He saw another opportunity to put his principles into practice and establish a genuinely philosophical government.

However, Dion fell under suspicion of plotting against Dionysius II, and royal distrust extended to Plato himself, who was held under detention for a year.

In 360 BC, Plato made his third and final political journey to Sicily. Summoned back by Dionysius II, Plato — now sixty-eight — left the Academy in the care of one of his disciples and travelled to Syracuse. Relations with the tyrant proved as difficult as before, and only the intervention of a warship dispatched by the Pythagorean Archytas secured his release.

Death and Influence

Towards the end of his life, Plato appears to have moved towards a more Pythagorean form of teaching, centred on mathematics and the Ideal Numbers. He had in fact paid a considerable sum to acquire three works on Pythagorean doctrine during his final visit to Sicily, which allowed him to deepen his understanding of it.

Plato died in Athens in 347 BC, during a wedding feast. He was at the time deep in the writing of Laws.

After his death he was revered as a divine figure, regarded as a son of the god Apollo.

All of Plato's works have survived. In the Middle Ages, however, few were translated into Latin, and so only a handful were widely read at the time — most notably the Timaeus.

With the exception of the Apology and the Letters, all are dialogues. They are conventionally grouped into three categories: early, middle and late dialogues.

Main Works

Gorgias
Meno
The Apology of Socrates
Symposium
The Republic
Phaedrus