What Did Military Service Teach Plato?

Philosophical illustration representing What Military Service Taught Plato

In short. What can be said about the lessons of war in Plato's thought, separating the thin evidence for his own service from the soldiers, courage and comradeship in his dialogues.

Nobody can say what military service “taught” Plato, because there is no first-hand account of it. Diogenes Laertius (III.8), writing more than five centuries after Plato’s death and citing Aristoxenus, says he fought at Tanagra, Corinth and Delium and won a prize for valour at Delium. Delium was fought in 424 BC, when Plato (born c. 428/427 BC) was about three years old, so at least part of this is wrong, and it may be confused with Socrates, who fought there. An Athenian of Plato’s class was likely to have served at some point in the Peloponnesian or Corinthian wars. Beyond that, “lessons” are either themes in the dialogues, which are evidence, or guesses about what was in his mind, which are not. This page keeps the two apart.

Training in Strategy and Tactics

There is no evidence that Plato was trained in strategy or tactics, or that he held any command, and the picture of a young Plato planning and executing manoeuvres is not supported by any ancient source. Ordinary Athenian soldiers fought in the ranks, and strategy was the business of the elected generals. What Plato does show is an interest in how soldiers are formed. The Republic spends much of Books II to IV on the education of the auxiliaries, and the Laws (I 625e-631a) discusses at length what an army and military training are for, arguing that the lawgiver should look to the whole of virtue, not courage in war alone. See his ideas about the philosopher-king for the contrast between rulers and soldiers.

Integration into Philosophical Theories

Conflict and justice are central themes in Plato, and they are treated in the dialogues in ways that could well reflect a lifetime lived through war and civil strife. But the textual anchors for his idea of justice are internal to the argument. In the Republic justice in the city is each class doing its own work (433a–434c), a definition set out by analogy with the soul, and is not derived from military hierarchies. A reader might notice that the working model is a city with a warrior class, and suspect an influence. That is a plausible interpretation, not documented fact.

In Plato’s dialogues the discussions of courage, governance and ethics appear in works like the Republic and the Laches. The nature of reality is a separate subject in which no military influence can be shown.

Lessons in Unity and Brotherhood

Comradeship in arms does appear as a theme in Plato, and it is in his text. In the Symposium (178e–179b) the speaker Phaedrus imagines an army made up of lovers and their beloved, who would be ashamed to disgrace themselves before each other and would be nearly invincible. In the Republic (416d–417b) the guardians live in common, with shared meals and no private property, like a garrison camped in the city. These passages show that Plato found the discipline of men fighting side by side a rich image for loyalty and shared purpose. Whether it was based on his own experience of camp life is something the texts do not tell us.

Reflection in Dialogues

Soldiers and war recur in the dialogues, but as settings and images, not as autobiography. The Symposium is a work about love, with a speech of Alcibiades describing Socrates in the campaigns at Potidaea and Delium (219e–221c). The Republic is about justice and the city. Neither is a reflection on “unity and brotherhood” drawn from the author’s military time, though both use the military setting. The disagreements among the speakers of the dialogues are shaped by Socratic argument and the conventions of the symposium and the conversation, and cannot be read as a record of negotiations Plato took part in as a soldier.

Experience of Conflict and Resolution

War certainly shaped the public life of the Athens Plato lived in, and he addresses its consequences. The Republic (466e–471c) treats war among Greeks as a kind of civil strife that should end in reconciliation, with limits on enslavement and destruction, and the Laws (I 628b, 629d) calls civil war the most bitter of wars. Those are claims in the text. The statement that Plato “mediated disputes” in the army, or “witnessed the destructive nature of unresolved conflict” on the battlefield, is not attested.

The better-documented source for his concern with conflict is political: the Seventh Letter (324b–326b), whose authenticity is debated, describes his disgust at the Thirty and at the democracy’s execution of Socrates in 399 BC.

Application in Theoretical Frameworks

If one wants to say what the Greek experience of war contributes to Plato’s thought, the safest claims concern his subjects, not his experience. The Laches examines courage, with two generals as speakers, and ends without a definition (190e–199e). The Republic defines courage as preserving, through pleasure and pain, a correct belief about what is to be feared (429a–430c), and makes it the virtue of the spirited part of the soul and of the auxiliary class. In the Laws (I 630a–631d) courage is ranked as the lowest of the four virtues, below wisdom, temperance and justice.

Plato’s account of the ideal city can be read as one where the military is subordinate to wisdom. Whether that reflects any personal lesson is a matter of interpretation. We can describe what Plato wrote with confidence. Why he wrote it we can only infer.

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