Socrates vs Thrasymachus
The first book of Plato's Republic stages a confrontation between Socrates and Thrasymachus, a sophist who argues that justice is nothing more than the advantage of the stronger. The exchange is the founding episode of Western political philosophy and a permanent reference point for every subsequent debate over moral realism.
Key differences at a glance
| Socrates | Thrasymachus | |
|---|---|---|
| What justice is | The right ordering of the soul, also the most rational and happy life. | The advantage of the stronger; laws made by rulers for themselves. |
| Verdict on the unjust life | Self-undermining: injustice within the soul disables the agent. | Profitable: the unjust prosper while the just are duped. |
| Place in Plato's Republic | Defends justice as integral to the well-ordered soul and city. | Stages the founding objection that the rest of the dialogue answers. |
Biographical facts
| Socrates | Thrasymachus | |
|---|---|---|
| Dates | 470 BC – 399 BC | c. 459 BC – c. 400 BC |
| Nationality | Greek | Greek |
| Era | Ancient | Ancient |
| Movements | Ancient Greek Philosophy | Sophism, Ancient Greek Philosophy |
| Profile | Socrates → | Thrasymachus → |
Where they agree
Both treat the question of what justice is as a proper subject of philosophical inquiry, both reject mythological accounts of right and wrong in favor of rational analysis, and both treat the political community as the natural setting for the exercise of justice. Both speak with the confidence of a person who believes he has seen through the conventional understanding of his contemporaries.
Where they disagree
Thrasymachus argues that justice is whatever serves the interest of the ruling power: laws are made by the strong for their own benefit, and the just person is the one who is duped into serving someone else's interest while the unjust person prospers. Socrates rejects the position by arguing that injustice within the soul, like injustice within the city, undermines the very capacity for action that the unjust person hopes to exploit, and that the truly just life is also the most rational and most happy. The exchange is the canonical instance of the philosophical defense of morality against the cynic, and it shapes the rest of the Republic.
Representative quotes
Socrates
-
“There is only one good, knowledge, and one evil, ignorance.”
Variant: The only good is knowledge and the only evil is ignorance. | Socrates II: xxxi . Original Greek: ἓν μόνον ἀγαθὸν εἶναι, τὴν ἐπιστήμην, καὶ ἓν μόνον κακόν, τὴν ἀμαθίαν -
“False words are not only evil in themselves, but they infect the soul with evil.”
Plato, Phaedo 115e -
“I only wish that wisdom were the kind of thing that flowed ... from the vessel that was full to the one that was empty.”
Plato , Symposium , 175d
Thrasymachus
-
“Listen, then. I say justice is nothing other than what is advantageous for the stronger.”
Plato , Republic , 338c -
“Plato , Republic , 338c”
Listen, then. I say justice is nothing other than what is advantageous for the stronger. -
Attributed to Thrasymachus:
“Justice is the advantage of the stronger.”
Continue reading
- Full profile: Socrates
- Full profile: Thrasymachus
- Shared movements: Ancient Greek Philosophy
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