Full Idea
The fool and the infant and the madman at times say something true, but they do not possess knowledge of the true.
Gist of Idea
Fools, infants and madmen may speak truly, but do not know
Source
Sextus Empiricus (Against the Logicians (two books) [c.180], I.042)
Book Reference
Sextus Empiricus: 'Against the Logicians', ed/tr. Bury,R.G. [Harvard Loeb 1997], p.21
A Reaction
This may be correct of someone who is insane, but seems unfair to the fool and the infant. At what age do children begin to know things? If speech was just random nonsense, an accidental truth seems impossible.