“And yet, O my friend, if true opinion in law courts and knowledge are the same, the perfect judge could not have judged rightly without knowledge; and therefore I must infer that they are not the same.”
Socrates argues that someone can arrive at a correct judgment on testimony without having witnessed or known the event firsthand. The example tests Theaetetus’s proposal that knowledge simply equals true opinion; the dialogue continues to investigate other proposed definitions rather than announcing a simple final formula.
Source details
Theaetetus, around Stephanus 201a–c, Socrates explaining his law-court counterexample while speaking with Theaetetus. Benjamin Jowett English translation, Project Gutenberg #1726. The full sentence is spoken by Socrates in the dramatic dialogue, not from Jowett’s prefatory commentary; no claim is made about modern evidence law.