Protagoras

Author: Plato · Year: c. 4th c. BCE (trans. Stanley Lombardo and Karen Bell, Hackett 1997) · Type: dialogue

"The dramatic masterpiece among Plato's 'Socratic' dialogues" (Cooper): young Socrates confronts the great sophist Protagoras over whether virtue (aretē, "the art of citizenship") can be taught. The dialogue's governing irony is a position-swap: Socrates opens doubting teachability; Protagoras, who teaches virtue for a fee, defends it — and by the end Socrates argues virtue is knowledge (hence teachable) while Protagoras resists, insisting courage is not knowledge. Along the way Plato stages Protagoras' Great Speech (the Prometheus myth grounding universal civic virtue), the problem of the unity of the virtues, and the climactic hedonic measuring-art that dissolves "weakness of will" (akrasia) into mere miscalculation. Nothing is settled — what virtue is is never defined — and the dialogue closes by reopening that prior question (361c), which Cooper's introduction connects forward to the Meno.

Core Arguments

  1. Claim: Don't entrust your soul to a sophist before knowing whether his teaching helps or harms it. Because: a sophist "peddles provisions upon which the soul is nourished" (313c), but unlike food you cannot inspect them first — "you take the teaching away in your soul by having learned it" (314b), helped or injured; so the buyer must already be "a physician of the soul." Against: Hippocrates' eager presumption that wisdom is simply a good to be bought. Location: 311b–314b.

  2. Claim (Socrates' opening case): virtue cannot be taught. Because: two observations — in the Assembly the Athenians take technical advice only from experts but accept civic counsel "from anyone," so they think virtue is not an expertise (319b–d); and the best men (Pericles) fail to transmit virtue to their sons, who "browse like stray sacred cattle" (319e). Against: Protagoras' Great Speech, which re-reads both data. Location: 319a–320b.

  3. Claim (Protagoras' Great Speech): civic virtue is distributed to everyone, not, like the crafts, to a few — and is acquired by teaching, not nature. Because: in the Prometheus myth, Zeus, fearing humans will destroy themselves, sends Hermes to give aidōs (shame) and dikē (justice) "to all," with the law "Death to him who cannot partake of shame and justice" (322d); and the practice of punishment — "not vengeance for a past wrong… but with a view to the future" (324b) — only makes sense if virtue is teachable. The Assembly's openness to all advisers is thus evidence for universal distribution. Against: that the universal must be inborn (refuted by the blame/punishment argument). Location: 320c–328c.

  4. Claim (the pivot): are justice, temperance, courage, piety, wisdom parts of one virtue (like parts of a face, each with its own function) or merely names for one thing (like parts of gold)? Because: the unity question must be fixed before teachability can be decided. Against: Protagoras chooses parts-of-a-face — "many are courageous but unjust" (329e) — resisting the reduction to one knowledge. Location: 329c–330b.

  5. Claim (Socratic intellectualism): the virtues reduce to knowledge, and so "no one does wrong willingly." Because: a chain of arguments (justice/piety near-identical, 330c–331b; wisdom = temperance via the one-opposite premise, 332a–333b) drives toward unity-as-knowledge; clinched later by "no one goes willingly toward the bad" (358d). Against: Protagoras assents "very grudgingly"; the one-opposite premise carries the weight and can be resisted. Location: 330c–333b; 358b–d.

  6. Claim (the hedonic measuring-art): "being overcome by pleasure" (akrasia) is incoherent; the phenomenon is ignorance, curable by an art of measurement (metrētikē technē) that weighs near and remote pleasures and pains — "our salvation in life." Because: if the good is the pleasant, "overcome by pleasure" becomes the absurd "overcome by the good" (355d); the only intelligible sense of "outweigh" is magnitude — and nearer pleasures loom larger as nearer objects look bigger (356c), so error is a misperception the measuring art corrects (356d–357e). Against: it presupposes pleasures and pains are commensurable on one scale, and the saving art is named but never produced ("we can inquire into later," 357c); whether Socrates endorses the hedonism or wields it dialectically is left open (the premise is repeatedly assigned to "the many"). Location: 351b–357e.

  7. Claim (the ironic reversal): the inquiry overturns both speakers — if virtue is wholly knowledge it must be teachable (Socrates' new view), yet Protagoras now denies the virtues are knowledge. Because: "the argument, if it had a voice of its own… would say, mockingly… how ridiculous you are, both of you" (361a) — and nothing is settled because what virtue is was never defined. Against: the deferral is deliberate — Socrates proposes to settle what virtue is before re-deciding teachability, "so that Epimetheus might not frustrate us a second time" (361c). (The forward link to the Meno is Cooper's editorial cross-reference, not something the dialogue itself states.) Location: 361a–c.

Key Findings

  • Plato stages "is virtue teachable?" twice, with non-converging machinery. The Protagoras answers via intellectualism + the measuring-art; the Meno via recollection + virtue as god-given "without understanding." Both end aporetic, because the prior question — what virtue is — is left open. See claims#plato-virtue-teachability-staged-twice.
  • The locus classicus for Plato's denial of akrasia. "No one errs willingly"; vice is cognitive error. This is in standing tension with the partitioned, appetite-bearing soul of the Gorgias and Republic IV. See claims#plato-moral-psychology-intellectualism-to-partition (live claim) and socratic-intellectualism.
  • "Measure saves" — on a hedonist premise. The metrētikē technē shares the structural role of measure-as-rescue with the Philebus and the Statesman, but its verdict on pleasure is the opposite (good = pleasure here; pleasure is apeiron and rejected there). See claims#plato-measure-saves-divergent-verdicts (live claim).
  • The Great Speech is a proto-social-contract account of universal civic virtue — aidōs and dikē given "to all" — grounding why everyone may be taught, blamed, and punished.

Concepts Developed

  • socratic-intellectualism — virtue is knowledge; the unity of the virtues; "no one errs willingly"; the denial of akrasia (the dialogue's most developed statement).
  • the-mean — the metrētikē technē / art of measurement as the hedonist cousin of the Statesman's and Philebus' measure-doctrines.

Concepts Referenced

  • anamnesis / maieutics — contrast: there is no recollection-doctrine and no midwifery here; the method is elenctic and agonistic (the threatened walkout; "you just want to win the argument," 360e).
  • peras-apeiron — the measure-saves structure, with the opposite verdict on pleasure.
  • mimesis — the Simonides interpretation (338e–347a) as a half-parody of sophistic literary criticism.

Key Passages

"a kind of merchant who peddles provisions upon which the soul is nourished" (313c) "anyone can stand up and advise them, carpenter, blacksmith, shoemaker" (319d) "his sons have to browse like stray sacred cattle and pick up virtue" (319e) "'To all,' said Zeus, 'and let all have a share'" (322d) — aidōs and dikē "Reasonable punishment is not vengeance for a past wrong… but… with a view to the future" (324b) "Parts as in the parts of a face… Or parts as in the parts of gold?" (329d) "someone does what is bad… having been overcome by the good" (355d) — akrasia dissolved "the art of measurement… would make the appearances lose their power by showing us the truth" (356d) "no one goes willingly toward the bad or what he believes to be bad" (358d) "Socrates and Protagoras, how ridiculous you are, both of you" (361a)

What's Not Obvious

  • The two speakers swap sides, and Plato says so out loud. The dialogue's drama is its argument: Socrates ends defending the teachability he set out to doubt, Protagoras ends denying the knowledge-thesis his profession presupposes (361a–b). The "comeuppance" exposes that teachability was always parasitic on the unanswered question what virtue is. See claims#plato-virtue-teachability-staged-twice.
  • The whole positive doctrine rests on an art "named but never produced." The metrētikē technē that is "our salvation in life" is invoked as the cure for akrasia (356d) but its content is deferred ("we can inquire into later," 357c) — Plato banks the conclusion on credit, and on the contested premise that good = pleasure.
  • "Man is the measure" is not in this dialogue. Protagoras' famous relativism is stated in the Theaetetus; here he delivers the Great Speech and defends the separability of the virtues. The protagoras entity page sources the relativism to the Theaetetus, not to the Protagoras.

Critique / Limitations

The unity arguments lean on a contested formal premise ("each thing has one opposite"); the first courage argument is a transparent illicit conversion that Protagoras cleanly rebuts (350c–351b) — Plato lets Socrates lose a round. The hedonic calculus presupposes a single commensurating scale for pleasure and pain and never specifies the saving art. Whether the hedonism is Socrates' own or "the many's," wielded against them, is genuinely undecidable from the text.

Connections

Sources

  • Protagoras, trans. Stanley Lombardo and Karen Bell, in Plato: Complete Works (Hackett, 1997), Stephanus 309a–362a; raw file lines 21789–22815.
  • Depth layer: wiki/sources/.extraction-plato-protagoras.md.