 “So long as”: to make the argument workable, we may suggest that its point is that the meanings of words are exempt from flux. If meanings are not in flux, and if we have access to those meanings, nothing stops us from identifying the whiteness at least until it flows away. But if meanings are in flux too, we will have the result that the argument against Heracleitus actually produces at 183a5: anything at all will count equally well as identifying or not identifying the whiteness. “Unless we recognise some class of knowable entities exempt from the Heracleitean flux and so capable of standing as the fixed meanings of words, no definition of knowledge can be any more true than its contradictory. Plato is determined to make us feel the need of his Forms without mentioning them” (Cornford 1935, 99).