There's not much to be done about the impossibility. One must instead get rid of the desire.

I am mainly concerned with unqualified knowledge, by contrast with the varieties of expert knowledge: scientific knowledge of various sorts, legal knowledge, medically expert knowledge, and so on.

Normal adults can doodle, amble, and drift with no need to assess risk, since there is normally no risk at all. Jazz improvisation seems less subject to standards of risk than surgery, and less than much formal athletic performance, as in a tennis match.

In my view there is a level of human knowledge that involves just getting it right aptly. This "animal" epistemic level is an inferior level in just the way of Diana's long shot in the dark while drunk. That shot is inferior in a certain respect if too poorly selected as a hunter's archery shot, even if not quite as poorly selected as would be a shot aimed at the moon. Even if Diana's too risky shot turns out to be apt by attaining success through sublime archery dexterity, it is still inferior in the particular respect of being so risky and hence so poorly selected.

When there are conflicts of observation, when experiments cannot be replicated, scientists may then retreat to a study of the various specific observations so as to explain the conflict, in the course of which they would make use of the concept of observation, or of some specification of that concept.

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.

In arriving at the relevant theory about the specifics of our faculty of vision we will presumably use our eyes to gather relevant data. Based on such data we come to know about the optic nerve, the structure of our eyes, the rods and cones, etc., so as to explain how it is that vision gives us reliable access to the shapes and colors of objects around us. In reliably arriving at that theory we thus exercise the very faculty whose reliability is explained by the theory. There is no vice in this sort of circularity.