Socrates: “I know that I know nothing”

“I know that I know nothing” is one of the most frequently quoted “Socratic” lines. It symbolizes intellectual humility and the core of the so-called Socratic method: rather than claiming we know, we should ask questions and test our own assumptions. Although it sounds simple, plenty of inaccuracies circulate around the phrase. Below you’ll find where it comes from, what it means in context, and what people commonly get wrong about it.

Its origin isn’t from a textbook, but from an oracle

The earliest context comes from Plato’s Apology of Socrates (Apologia). Socrates recounts the story of the Delphic Pythia, who is said to have declared Socrates “the wisest.” Socrates doesn’t simply take it on faith—he investigates, questioning craftsmen, politicians, and poets. The result? Many “don’t know something, yet think they do.” Socrates therefore concludes that he is “a little wiser,” because “I neither know nor think that I know” (Apology 21d–e). This emphasis on unfeigned ignorance lies at the heart of the saying we paraphrase today. (Full text and translation. (The Center for Hellenic Studies)

Is “I know that I know nothing” an authentic quote?

The short answer: you won’t find it in Plato in those exact words. It’s a later, shortened paraphrase. The formulation “ipse se nihil scire id unum sciat” (literally: “that he knows nothing; the one thing he knows is this”) appears in Cicero’s Academica. From there it spread in the Latin world and was later “re-Greeked” into the form “[hen oida hoti] ouden oida”—“[one thing I know: that] I know nothing.” (Latin text: (Latin Library)

What did Socrates mean by it?

Socrates is not celebrating ignorance. He is saying that he doesn’t pretend to know what he doesn’t know, and that this is precisely what distinguishes him from many of his contemporaries. In practice it looks like this: by questioning (elenchos), he dismantles confident claims until it becomes clear what is vague, contradictory, or unjustified. This is philosophy as a craft: knowing where the limits of my understanding are, and methodically pushing them.

“But Socrates says he does know something”

In the same Apology, Socrates also appeals to certain firm moral convictions. At 29b–c, for example, he says that he knows it is worse to commit injustice and to disobey a better one (god or man) than to face the uncertain evil that is death. So this isn’t nihilism. He doesn’t deny all knowledge; rather, he rejects unwarranted certainty where evidence is lacking. (Apology in translation. (The Center for Hellenic Studies)

The most common misconceptions about the saying

• “Socrates said it word for word.” Not in this form. It’s a paraphrase that became established in Latin with Cicero (Academica 1.16). In Plato’s Apology you’ll find a close equivalent: “I neither know nor think that I know” (21d–e). Sources for Cicero: (Latin Library, The Center for Hellenic Studies)
• “Socrates claimed he knows absolutely nothing.” No. In the Apology he explicitly endorses certain moral insights (29b–c). The point isn’t to deny knowledge, but to reject pretend knowledge. (Apology—full text and context: (The Center for Hellenic Studies)
• “It’s a modern-era quote.” No. The ancient tradition knew it—already Diogenes Laertius in Lives and Opinions of Eminent Philosophers attributes to Socrates that he “knew nothing—except that he knew just that” (II.32). Text (Greek/English notes, penelope.uchicago.edu)
• “So it implies relativism: everything is just opinion.” Socrates isn’t a relativist. Rather, he is a methodical skeptic in areas where good justification is lacking, while still believing that through the hard work of reason we can get closer to better answers. For a broader context, see the scholarly overview: Stanford Encyclopedia of Philosophy – Socrates: (Stanford Encyclopedia of Philosophy)

How to use the saying today

• Intellectual humility as a skill: if we admit uncertainty, we learn better, correct mistakes, and watch out for “confident delusions.”
• Discussion instead of declarations: ask about definitions (“What exactly do you mean?”), reasons (“Why do you think that?”), and implications (“What would follow from that?”).
• Distinguishing domains of knowledge: in some areas we know a lot (practice, data), in others little—and that’s fine. The point is not to pretend.

Where can I find it in the text?

• Apology 21d–e: “I neither know nor think that I know,” the outcome of confronting those with a “reputation for wisdom.” (The Center for Hellenic Studies)
• Apology 29b–c: Socrates says he knows it is worse to commit injustice than to face death. (The Center for Hellenic Studies)
• Apology 38a: “The unexamined life is not worth living”—the ethical conclusion of his practice (you’ll find it in the same text). (The Center for Hellenic Studies)

Quick FAQ

Is “I know that I know nothing” a paradox?
Only if we read it as a logical claim about all knowledge. Socrates lives it in practice: he acknowledges limits so he can grow.

Is it a call to study nothing?
On the contrary—it’s a call to study honestly and without pretense.

Why has it survived for centuries?
Because it’s a guide to responsible thinking: before sharing ready-made “truths,” look for better reasons and more precise concepts. The person who does that is “a little wiser” than the one who merely thinks they know.

Videos on the topic

WIRELESS PHILOSOPHY: The Examined Life: Know Thyself – the context of the “examined life.”

TED-Ed: This tool will help improve your critical thinking, the Socratic method of questioning in practice.

See U in History: Socrates – The Philosopher Who Knew He Knew Nothing, a popular retelling of the story.

Sources

1. Plato – Apology (translation and annotated passages). Center for Hellenic Studies (Harvard University). https://chs.harvard.edu/primary-source/plato-the-apology-of-socrates-sb/
2. D. Nails: Socrates. Stanford Encyclopedia of Philosophy. https://plato.stanford.edu/entries/socrates/
3. Marcus Tullius Cicero – Academica 1.16 (Latin text). The Latin Library. https://www.thelatinlibrary.com/cicero/acad.shtml
4. Diogenes Laertius – Lives of Eminent Philosophers II.32 (Socrates). University of Chicago – Bill Thayer. https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Diogenes_Laertius/2/Socrates*.html