For sophistry is of three kinds:
One kind consists in denying realities and any knowledge of them. More extreme than this is the statement of one who says of the Necessary Existent, the Eternal Creator:
“He is neither existent nor non-existent.”
Such people contradict themselves, for they categorically affirm that no categorical affirmation can be made.
Another kind is the position of those who profess ignorance—the agnostics who suspend judgment—saying:
“We do not know whether any reality (1) or knowledge exists.”
More extreme than this is the statement of one who says:
“I do not know, nor will I say whether He is existent or non-existent, living or dead.”
A third kind is the position of those who make realities dependent upon beliefs. The first group denies them; the second suspends judgment concerning them; and the third makes them dependent upon people’s conjectures (2).
A fourth group has also been mentioned: those who say that the world is in constant flux and therefore affirm no fixed reality for it. They belong to the first group, but this is what their position entails (3).
The point here is that a person’s withholding judgment between two contradictories does not entail the negation of both.