Logic chases truth up the tree of grammar. - Willard Van Orman Quine

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

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

How are we to adjudicate among rival ontologies? Certainly the answer is not provided by the semantical formula "To be is to be the value of a variable"; this formula serves rather, conversely, in testing the conformity of a given remark or doctrine to a prior ontological standard.