Students of the heavens are separable into astronomers and astrologers as readily as the minor domestic ruminants into sheep and goats, but the separation of philosophers into sages and cranks seems to be more sensitive to frames of reference.
Willard Van Orman QuineLinguistically, and hence conceptually, the things in sharpest focus are the things that are public enough to be talked of publicly, common and conspicuous enough to be talked of often, and near enough to sense to be quickly identified and learned by name; it is to these that words apply first and foremost.
Willard Van Orman QuineThe scientist is indistinguishable from the common man in his sense of evidence, except that the scientist is more careful.
Willard Van Orman Quine