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Two thinkers, side by side

Life

Protagoras

c. 490 BCE – c. 420 BCE

ClassicalSocratic

Born Abdera

Man is the measure of all things. The first and greatest of the Sophists turned philosophy toward human judgment.

Plato

c. 428 BCE – c. 348 BCE

ClassicalPlatonist

Born Athens

He saw a world behind the world. The Forms are real; what we see are shadows.

Connection

Protagoras the man-measure doctrine answered Plato — Plato gave Protagoras two dialogues and treated 'man is the measure of all things' as the most serious rival to his own position. He preserved the doctrine in the very act of trying to refute it.

Shared Ideas

Justice

Shared Places

Athens Athens Athens

Ideas

Skepticism Justice

Justice Being Virtue Reason Logos Change The Republic The Virtuous City

Words

“Man is the measure of all things: of things that are, that they are, and of things that are not, that they are not.”
— Protagoras

“Concerning the gods, I have no means of knowing whether they exist or not, nor what form they might take; for there is much to prevent knowledge: the obscurity of the subject and the shortness of human life.”
— Protagoras

“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
— Plato

“The measure of a man is what he does with power.”
— Plato

Key Moments

c. 490 BCE

Born in Abdera

c. 460 BCE

Becomes the first professional Sophist

c. 450 BCE

Teaching in Athens

c. 440 BCE

Writes On the Gods

c. 428 BCE

Born in Athens

c. 408 BCE

Meeting Socrates

399 BCE

Death of Socrates

c. 388 BCE

First Voyage to Syracuse

Works

Fragments & Testimonies

Apology

Crito

Euthyphro

Protagoras

Symposium

Meno

Phaedo

Gorgias

Republic

Phaedrus

Theaetetus

Explore

Compare

Two thinkers, side by side

Life

Protagoras

c. 490 BCE – c. 420 BCE

ClassicalSocratic

Born Abdera

Man is the measure of all things. The first and greatest of the Sophists turned philosophy toward human judgment.

Plato

c. 428 BCE – c. 348 BCE

ClassicalPlatonist

Born Athens

He saw a world behind the world. The Forms are real; what we see are shadows.

Connection

Shared Ideas

Justice

Shared Places

Athens Athens Athens

Ideas

Skepticism Justice

Justice Being Virtue Reason Logos Change The Republic The Virtuous City

Words

“Man is the measure of all things: of things that are, that they are, and of things that are not, that they are not.”
— Protagoras

“Concerning the gods, I have no means of knowing whether they exist or not, nor what form they might take; for there is much to prevent knowledge: the obscurity of the subject and the shortness of human life.”
— Protagoras

“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
— Plato

“The measure of a man is what he does with power.”
— Plato

Key Moments

c. 490 BCE

Born in Abdera

c. 460 BCE

Becomes the first professional Sophist

c. 450 BCE

Teaching in Athens

c. 440 BCE

Writes On the Gods

c. 428 BCE

Born in Athens

c. 408 BCE

Meeting Socrates

399 BCE

Death of Socrates

c. 388 BCE

First Voyage to Syracuse

Works

Fragments & Testimonies

Apology

Crito

Euthyphro

Protagoras

Symposium

Meno

Phaedo

Gorgias

Republic

Phaedrus

Theaetetus