It is the stone which tests gold when it is rubbed against it. Thus Antiphon[1] and Pindar[2] and Sophokles.[3] But Hyperides calls ba/sanoi the things said in interrogation by those who are being tested and written up.[4]
And [there is] a proverb: Test stone, in reference to those investigating things in words or in deeds; since the Lydian stone tests gold.[5]
[Note] that those outside say: "'let the disagreement depend on a verdict, let the verdict test the arguments, let the test set the boundaries on what is necessary, let the boundary be written, let what is written be validated, let what has been validated be corroborated in deeds, and let all quarreling disappear, and let friendship parade back in.' And it is necessary not to reach the verdicts without circumspection."[6]