Linguistically, 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 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 QuineEnglish general and singular terms, identity, quantification, and the whole bag of ontological tricks may be correlated with elements of the native language in any of various mutually incompatible ways, each compatible with all possible linguistic data, and none preferable to another save as favored by a rationalization of the native language that is simple and natural to us.
Willard Van Orman Quine