When I accept someone's testimony, I am thus only a small part of the full seat of epistemic competence, which might include many others in a long chain. My own contribution might then be slight, just through the perceptual and linguistic competence involved in knowing what someone is saying or writing, etc.

You attain aptness by judging while in good shape and in a good situation (good light, good distance, etc.), through the exercise of good barn-sorting epistemic competence.

Animal knowledge is metaphysically constituted by apt belief, by belief whose correctness manifests the believer's epistemic competence, a relevant disposition to get it right on the matter at hand when one tries to do so.

Any defense of common sense must allow that it is revisable.

Through our perceptual systems, we represent our surroundings, aiming to do so accurately, where the aiming is functional or teleological, rather than intentional. And the same goes for our functional beliefs. Through our judgments, however, we do intentionally, even consciously, attempt to get it right.

We need some standard that will determine how likely a belief is to be true given just that it is stored in one of us, including strangers that one can ask for directions, and with whom one might collaborate.

It is bad to want something that not even God could attain, especially when the impossibility becomes obvious.