Possibly, but my concern is that there not be more things in my philosophy than are in heaven and earth. - Willard Van Orman Quine

Implication is thus the very texture of our web of belief, and logic is the theory that traces it.

Our argument is not flatly circular, but something like it. It has the form, figuratively speaking, of a closed curve in space.

The issue over there being classes seems more a question of convenient conceptual scheme; the issue over there being centaurs, or brick houses on Elm Street, seems more a question of fact. But I have been urging that this difference is only one of degree, and that it turns upon our vaguely pragmatic inclination to adjust one strand of the fabric of science rather than another in accommodating some particular recalcitrant experience. Conservatism figures in such choices, and so does the quest for simplicity.