To this question no answer is given. But Sokrates, — after remarking on the confused and unphilosophical manner in which the debate has been conducted, both he and Theætêtus having perpetually employed the words know, knowledge, and their equivalents, as if the meaning of the words were ascertained, whereas the very problem debated is, to ascertain their meaning[113] — takes up another path of enquiry. He distinguishes between possessing knowledge, — and having it actually in hand or on his person: which distinction he illustrates by comparing the mind to a pigeon-cage. A man hunts and catches pigeons, then turns them into the cage, within the limits of which they fly about: when he wants to catch any one of them for use, he has to go through a second hunt, sometimes very troublesome: in which he may perhaps either fail altogether, or catch the wrong one instead of the right. The first hunt Sokrates compares to the acquisition of knowledge: the second, to the getting it into his hand for use.[114] A man may know, in the first sense, and not know, in the second: he may have to hunt about for the cognition which (in the first sense) he actually possesses. In trying to catch one cognition, he may confound it with another: and this constitutes false opinion — the confusion of two cognita one with another.[115]
[113] Plato, Theæt. p. 196 D.
[114] Plato, Theæt. p. 197-198.
[115] Plato, Theæt. p. 199 C. ἡ τῶν ἐπιστημῶν μεταλλαγή.
Sokrates refutes this. Suggestion of Theætêtus — That there may be non-cognitions in the mind as well as cognitions, and that false opinion may consist in confounding one with the other. Sokrates rejects this.
Yet how can such a confusion be possible? (Sokrates here again replies to himself.) How can knowledge betray a man into such error? If he knows A, and knows B — how can he mistake A for B? Upon this supposition, knowledge produces the effect of ignorance: and we might just as reasonably imagine ignorance to produce the effects of knowledge.[116] — Perhaps (suggests Theætêtus), he may have non-cognitions in his mind, mingled with the cognitions: and in hunting for a cognition, he may catch a non-cognition. Herein may lie false opinion. — That can hardly be (replies Sokrates). If the man catches what is really a non-cognition, he will not suppose it to be such, but to be a cognition. He will believe himself fully to know, that in which he is mistaken. But how is it possible that he should confound a non-cognition with a cognition, or vice versâ? Does not he know the one from the other? We must then require him to have a separate cognition of his own cognitions or non-cognitions — and so on ad infinitum.[117] The hypothesis cannot be admitted.
[116] Plato, Theæt. p. 199 E.
[117] Plato, Theæt. p. 200 B.
We cannot find out (continues Sokrates) what false opinion is: and we have plainly done wrong to search for it, until we have first ascertained what knowledge is.[118]
[118] Plato, Theæt. p. 200 C.