Kan vi lära oss något nytt?

Idag har jag ägnat lite tid åt att fundera på Menos paradox, från Platons dialog Meno. Så här uttrycks den (vid 80d—e):

Meno

Why, on what lines will you look, Socrates, for a thing of whose nature you know nothing at all? Pray, what sort of thing, amongst those that you know not, will you treat us to as the object of your search? Or even supposing, at the best, that you hit upon it, how will you know it is the thing you did not know?

Socrates

I understand the point you would make, Meno. Do you see what a captious argument you are introducing — that, forsooth, a man cannot inquire either about what he knows or about what he does not know? For he cannot inquire about what he knows, because he knows it, and in that case is in no need of inquiry; nor again can he inquire about what he does not know, since he does not know about what he is to inquire.

Frågan är hur vi kan skaffa oss ny kunskap om x. Om vi redan känner till x kan vi inte skaffa oss ny kunskap om x. Om vi inte känner till x kan vi inte heller skaffa oss ny kunskap om x, eftersom vi inte vet vad vi kan skaffa mer kunskap om.