Key thinker: Plato (428/427 BC–348/347 BC)

Plato (428/427 BC–348/347 BC)


Plato was born into a distinguished aristocratic family in Athens sometime around 428/427 BC ( Little is known about Plato’s early life, but we do know that he experienced the Peloponnesian war and came of age around the time of Athens’ defeat by Sparta ( As a young man, Plato was taught by Socrates and became one of his followers (see 2.2.1. Socrates). Like some of Plato’s family members, Socrates was associated with the Thirty Tyrants, a group of conservative pro-Spartan oligarchs who briefly overthrew Athenian democracy in 404-403 BC ( In 399 BC, Socrates was sentenced to death on the charges of impiety, undermining democracy and corrupting the youth of Athens ( Since Socrates never recorded anything in writing, much of what we know about his philosophy is derived from the writings of others, such as Plato himself (see 2.2.2. Plato).

After Socrates’ death, Plato travelled extensively across Italy, Sicily, and possibly Greece and Egypt before returning to his native Athens to establish the school that came to be known as ‘the Academy’ ( Alongside philosophy, Plato taught subjects such as science, mathematics, and astronomy. Aristotle arrived at the Academy when he was 17 years old and taught and studied alongside Plato for the last 20 years of his teacher’s life (see Chapter 3 on Aristotle). In 367 BC Dionysus II, a relative of Plato’s friend Dion, became the ruler of Syracuse and Plato accepted an invitation to teach him how to become the sort of ‘philosopher king’ described in The Republic. The appointment was a failure and Plato quickly became embroiled in political intrigues. After Dion was exiled for sedition, Plato was placed under house arrest as a ‘personal guest’ of the ruler ( Plato was eventually allowed to return to his Academy in Athens where he remained until his death.


The Socrates who appears in almost all of Plato’s writing does not correspond to the historical figure of Socrates. Rather, Plato uses the character of Socrates and the latter’s dialectical method to interrogate prevailing ideas and assumptions about the world and society, and to offer alternative answers ( Plato’s The Republic, his most famous dialogue, is a perfect example of this method. In the dialogue, which purports to be a record of a discussion between Socrates and various citizens of Athens, the character of Socrates offers a lengthy critique of Athenian social institutions like democracy, private property, and the family, to show that these either need to be abolished or transformed ( Moreover, the Socratic dialectical method of inquiry exposes the deficiency of the standard definitions of key principles such as justice or the good life that Athenian citizens hold dear. While conversations of this sort certainly happened during Socrates’ life, the conclusions that arise from the dialogues seem to have been supplied by Plato, who shared the former’s distrust for rule by the many (

Plato’s designs for an ideal state are closely related to his theory of forms (see 2.3.2. The Allegory of the Cave). Plato argues that Forms are abstract objects that exist outside of space and time. They are perfect examples of properties that correspond to their real-world counterparts (see Chapter 1 on Aristotle’s theory of forms). The realm of genuine knowledge is located at the level of Forms, which Plato considers to be more real than the physical world because they are unchanging and transcend space and time ( Forms are eternal, perfect concepts that are not subject to people’s beliefs but are the true essence of things, while the physical world is merely a reflection or shadow of this other reality. For Plato, the task of philosophy is to uncover the nature of Forms and how they relate to one another. The philosopher, then, can make intelligible a higher reality of Forms that is not immediately tangible ( The highest Form is that of the Good, which is actualized in the establishment of a city that is governed by perfect justice (505a-b). Because philosophers are the only ones who can truly understand the nature of the Good (a Form), they are given the task of governing Plato’s ideal state.

The Republic outlines the institutions of an ideal state in which people occupy roles that correspond to their personal attributes (see 2.3.1. The Ideal State). For Plato, the state, like the human soul, contains three elements: the philosophic, the spirited, and the appetitive (Republic, 37b-441c). Plato argues that rulers should be wise; soldiers (auxiliaries) should be brave, without being reckless; and that ordinary people (farmers and artisans), who are governed by their appetites, should be constrained by the city’s government. The harmonious and just society that Plato describes in his dialogue is one where ‘philosopher kings’—philosophers who prefer contemplation over the actual governance of the city—rule over the two other social classes, the soldiers and those who produce the city’s subsistence goods (374d-376e). According to Plato, these rigid social hierarchies are kept in place by myths that reinforce the conviction that certain individuals are destined to occupy the role that society has allotted to them. Education is another pillar of Plato’s ideal state: the philosopher-rulers educate each social class according to its vocation. Future rulers should therefore receive a rigorous education, while ordinary people barely need to be educated at all. To ensure that the rulers are not tempted to use their power to exploit the other classes, however, they are taught to regard property with contempt.

Plato’s Republic has been criticized for its authoritarianism and its celebration of rigid structures that prevent social mobility. The idea that a harmonious functioning of the state is only possible if the overwhelming majority of citizens stick to the roles which are assigned to them at birth ensures that a certain aristocratic class holds power over others, like workers, women, or enslaved people, whose only job is to cater to this aristocratic class (Robinson, 2019). Moreover, the decision of who should occupy what social position incorporates prejudices about the ability of women, for example, to serve as soldiers since they are considered irrational and inferior to men in Plato’s philosophy (see 2.3.3. Women Guardians in the Ideal State). Plato’s theory of Forms also implies that acquiring knowledge about the world requires us to turn away from the world of the senses. But this excludes knowledge about racism, classism, and misogyny that is produced by those, like Sojourner Truth (see 2.2.3. Sojourner Truth), who experience its effects and communicate this experience through the story of their life. Like Aristotle, Plato has been subject to public scrutiny in recent years, as students and academics have re-assessed the illiberal aspects of his philosophy ( While Plato’s important contributions to philosophy cannot be denied, we must read his work alongside feminist and anti-racist thinkers who have tried to envision a more just and egalitarian world.

Further reading

Fine, Gail (ed.), 2019, The Oxford Handbook of Plato, Oxford: Oxford University Press.

Zuckert, Catherine H., 2009, Plato’s Philosophers: The Coherence of the Dialogues, Chicago: University of Chicago Press.

Robinson, Cedric J., “Slavery and the Platonic Origins of Anti-Democracy”, In Robinson, On Racial Capitalism, pp. 127-146. 

Roy Jackson, Plato: A Beginner's Guide, Hodder & Stoughton, 2002. 

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