There isn't a formal definition of success.

Ultimately, my more significant agreement is with a virtue tradition that features Aristotle and Descartes.

The data on which philosophical theorizing is based are rather the intuited contents themselves, concerning the various thought experiments. At least that is so outside the epistemology of the a priori.

Arguably, if you view a real barn in bright sunlight and close by, while fully alert and otherwise in good shape, then you do know whether or not you see a barn. You have "animal" knowledge, says my virtue theory, through the first-order aptness of your judgment.

There is no need for the scientist to go into whether an observation was made, nor into the who, what, when, or where. The data on which scientific theorizing is based are rather the propositional contents of the instrument readings recorded, or the facts detected thereby.

When we speak of ordinary unqualified knowledge, my thought is that we are implicitly relativizing to the standards imposed by our evolution-derived humanity. These are standards that determine when we consider it appropriate to store beliefs just as a human being, rather than in one's capacity as an expert of one or another sort. Such stored beliefs are to be available for later use in one's own thought or in testimony to others.

If a shot aimed at aptness succeeds aptly, it is then fully apt, since it is not only apt but also aptly apt. But the full aptness of such an attempt is entirely compatible with its being a horrible murder, if the "hunter" is an assassin and the prey his victim. That hunter's shot may still be outstandingly, fully apt, if it manifests the agent's competence in both archery dexterity and shot selection.