Fallibilism vs. Cynicism

In this related article, I write:

If we could not speak the truth, our minds would have to have some subconscious mechanism that evaluates our ideas and detects and rejects true ones, or modifies them a bit to introduce errors, before we become aware of them. Otherwise, we could still utter the truth, if only “by chance”, as Xenophanes says. Such a mechanism would itself depend on a criterion of truth. So the epistemological cynics, though inspired by Popper’s fallibilism, and even though they would call themselves ‘fallibilists’, are not actually fallibilists. Whether they realize it or not, they rely on the existence of a criterion of truth and (simultaneously, ironically) reject the possibility that some of our knowledge is true.