Today’s Dilbert has the devious Wally flouting Grice’s maxim of Quantity: (On Grice’s maxims, see this posting.) Saying “not two” implicates — conversationally implicates — not two or more, but Wally disregards this in favor of treating not two as ‘not exactly two’. But the pointy-headed boss has enough experience with Wally to suspect his deviousness.