Some have said that the thesis [of indeterminacy] is a consequence of my behaviorism. Some have said that it is a reductio ad absurdum of my behaviorism. I disagree with this second point, but I agree with the first. I hold further that the behaviorism approach is mandatory. In psychology one may or may not be a behaviorist, but in linguistics one has no choice.
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 QuineTheory may be deliberate, as in a chapter on chemistry, or it may be second nature, as in the immemorial doctrine of ordinary enduring middle-sized physical objects.
Willard Van Orman QuinePhysical objects are conceptually imported into the situation as convenient intermediaries not by definition in terms of experience, but simply as irreducible posits comparable, epistemologically, to the gods of Homer . . . For my part I do, qua lay physicist, believe in physical objects and not in Homer's gods; and I consider it a scientific error to believe otherwise. But in point of epistemological footing, the physical objects and the gods differ only in degree and not in kind. Both sorts of entities enter our conceptions only as cultural posits.
Willard Van Orman QuineThe familiar material objects may not be all that is real, but they are admirable examples.
Willard Van Orman QuineThe variables of quantification, 'something,' 'nothing,' 'everything,' range over our whole ontology, whatever it may be; and we are convicted of a particular ontological presupposition if, and only if, the alleged presuppositum has to be reckoned among the entities over which our variables range in order to render one of our affirmations true.
Willard Van Orman Quine