"Justice is nothing other than the advantage of the stronger"

Thrasymachus' thesis

Plato c. 428 BC · c. 348 BCBeyond appearances, the eternal Forms.

What it claims

Justice is the same thing everywhere: the advantage of the stronger. Being just means serving someone else's good, that of the one in command.

Why

Every government makes laws in its own interest and calls "just" what serves it: so justice is the interest of the stronger.

The same idea through history

Plato375 BCRepublic, book I: the version presented here, spoken by Thrasymachus, a real sophist (a teacher of rhetoric) of the time. It is not Plato's position: the whole rest of the Republic tries to refute it.

Plato387 BCGorgias, 483b-484a: Callicles, another of Plato's characters, says almost the opposite: it is the weak and the many who make the laws, to stop the strong from having more than them. But he shares the basic idea: the justice of the laws serves the interest of those who make them. The Gorgias is probably a little older than the Republic.

Karl Marx1846The German Ideology (with Engels): "the ideas of the ruling class are in every epoch the ruling ideas". The ideas of law and morality of an era serve the ruling class.

Friedrich Nietzsche1887Genealogy of Morality: closer to Callicles than to Thrasymachus. Our morality of "good" and "evil" would have been born from the revolt of the weak against the strong.

In short

""Justice is nothing other than the advantage of the stronger"" is an argument by Plato (Republic, I, 338c-344c (c. 375 BC), 375 BC) on the question "What makes something right?" (answer: morality questioned). Its claim: Justice is the same thing everywhere: the advantage of the stronger. Being just means serving someone else's good, that of the one in command. According to AskPhilosophy's logic check (Z3 solver), the argument is valid only if one grants a premise the author leaves unstated (P4). AskPhilosophy presents 4 objections, 1 of them with a documented reply, and the original text behind each premise, checked word for word.

Republic, I, 338c-344c (c. 375 BC)

Valid with an implicit premise

Socrates and his friends have been discussing what justice is for a while. Thrasymachus, a sophist, can stand it no longer: he hurls himself upon them "like a wild beast" (336b) and throws out his definition. Justice? It is nothing other than the advantage of the stronger. Those in power decide what is just, and they decide it for themselves.

click a premise to reject it

If you accept every premise, logic forces you to accept the conclusion. So the debate is about the premises.

Checked by a logic solver: the premises cannot all be true while the conclusion is false.
Without the implicit premise: Without P4, the computer finds a world where the laws do serve the powerful, but where there are also just actions the law does not command: helping a stranger, refusing to obey a cruel law. In that world, justice is not only the advantage of the stronger.

The argument is valid once P4 is added. Thrasymachus shows that laws serve those who govern. To conclude that justice is "nothing other" than that, he must assume there is no justice above the laws. That is what Cicero attacks. Socrates mainly attacks P2: do rulers really always seek their own interest? P3 is not logically essential: it describes how power imposes its justice (by punishing).

Analogy. In a playground, the oldest children set the rules of football: they pick the teams and decide whether there was a foul. They call anyone who objects a "cheat". For Thrasymachus, all rules of "justice" are like these.

Objections

Each objection is a conversation: click to see who replies and where the debate stands.

Socrates (Plato's character) 375 BC · attacks premise 2

Rulers can make mistakes. Sometimes they make laws that harm them. Yet you say it is just to obey the laws. So it is sometimes just to do what harms the stronger, the opposite of your definition.

Platon replies

Thrasymachus (Plato's character) 375 BC · Thrasymachus clarifies: the ruler "in the strict sense"

A physician who errs is not a physician at the moment he errs: it is his knowledge that abandons him. Strictly speaking, no craftsman errs. Likewise, the ruler, insofar as he is a ruler, does not err: he enacts the law that is best for himself, and that is what the subject must do.

Socrates (Plato's character) 375 BC · Socrates turns the physician example around

Let us take the physician in the strict sense, then: he heals the sick, he is not out to make money. Each art seeks the good of what it deals with: medicine, that of the body; the pilot, that of the sailors. So no ruler, insofar as he rules, seeks his own advantage, but that of those he rules.

See the rest of the debate (2)

Thrasymachus (Plato's character) 375 BC · The shepherd and the sheep

Do you think shepherds fatten their sheep for the good of the sheep? They do it for themselves and their masters. Real rulers look at the governed as one looks at sheep, and think night and day only of profiting from them. Justice is another's good: the advantage of the stronger, and a harm to the one who obeys.

Socrates (Plato's character) 375 BC · The shepherd as shepherd

You did not keep to your own precision. The shepherd as shepherd thinks only of the good of his flock; the one who thinks of the feast or the sale acts as a gourmet or a merchant, not as a shepherd. Likewise, every form of rule, as rule, seeks the good of what it governs. That is also why people demand pay for ruling: they know they work for others.

The debate goes on (our summary) Many readers find that Socrates wins on words more than on substance: the "ideal" ruler may serve his subjects, but Thrasymachus is speaking of real rulers. Glaucon himself admits it at the start of book II: Thrasymachus gave up too soon, and he takes up the thesis in another form (see "The ring of Gyges").

Cicero 52 BC · attacks premise 4

The height of folly is to think everything just that is laid down in the laws of peoples. Even the laws of tyrants? If the Thirty had imposed their laws on Athens, and even if all Athenians liked them, would they be just for that? There is only one justice, right reason commanding and forbidding. If justice were merely obeying the laws and everything were measured by interest, anyone would break the laws as soon as he saw profit in it.

no reply

No reply possible: objection raised in -52, after the author's death (-348).

The debate goes on (our summary) Thrasymachus could not reply (Cicero writes more than three centuries later). A supporter of his thesis would say that this "right reason" above the laws is itself a convenient idea for those who define it. But Cicero's question is hard to dodge: if we can say "this law is unjust", then we have an idea of justice that does not come from the law.

Callicles (Plato's character, in the Gorgias) 387 BC · attacks premise 2

It is not the strong who make the laws, but the weak and the many. They make them in their own interest, and to frighten the stronger they tell them that it is shameful and unjust to want more than others. By nature, on the contrary, it is right for the better to have more than the worse.

no reply

Platon never answered this objection.

The debate goes on (our summary) Callicles contradicts Thrasymachus on one point (who makes the laws?) but agrees with him on the essential: the justice of the laws is the interest of those who make them. Both theses come back much later: Thrasymachus' version in Marx (the ruling ideas are those of the ruling class), Callicles' version in Nietzsche (slave morality).

Socrates (Plato's character) 375 BC · attacks the conclusion

Can a city, an army, or even a band of robbers and thieves achieve anything if its members wrong one another? Injustice breeds hatred and strife; justice, concord and friendship. Even to do wrong together, a little justice among oneselves is needed.

no reply

Platon never answered this objection.

The debate goes on (our summary) Thrasymachus grudgingly accepts ("so be it, not to differ from you"), without being convinced. One can grant him a point: the band of robbers needs justice among its members, not towards its victims. The argument shows that justice is useful to a group, not that it is anything other than the advantage of the stronger.