How can such confusions even occur? Plato presents a dilemma that seems to show that they can’t. The objects of the judgement, O1 and O2, must either be known or unknown to the judger x. Suppose one of the objects, say O1, is unknown to x. In that case, O1 cannot figure in x’s thoughts at all, since x can only form judgements using objects that he knows. So if O1 is not an object known to x, x cannot make any judgement about O1. A fortiori, then, x can make no false judgement about O1 either.