Quine, Willard Van Orman

"To be is to be the value of a variable."

"The problem of induction is to justify the rules by which we project unobserved instances from observed ones."

"Ontology is what one says exists; ideology is how one says one determines what exists."

"There is no fact of the matter about how language actually carves up the world."

"We cannot significantly assert or deny that the space and time of physics are the same as the space and time of sense experience."

"Language is a social art which we all acquire on the evidence solely of other people's overt behavior."

"The law of non-contradiction is not an explanation of anything; it is part of our conceptual scheme."

"I view science as a linguistic enterprise organized by pragmatic and aesthetic principles."

"Common sense is a collection of practices and intuitions refined by experience and corrected by science."

"The analytic-synthetic distinction cannot be maintained in any clear form."

"Words can mean different things in different contexts; meaning is use."

"Indeterminacy of translation shows that there is no fact of the matter as to how to translate between languages."

"Every object, even the most abstract, has a place in a vast conceptual scheme."

"The purpose of science is not to solve the riddle of the universe but to reduce the data of experience to a simple and manageable form."

"We must be ontologically committed to whatever our theory says exists."

"Translation is only approximate because meanings are not determinate."

"Logic can be revised just as any other part of our theory can be revised."

"Mathematics is not about abstract objects; it is a convention for organizing experience."

"The web of belief is a totality that must be evaluated as a whole, not piecemeal."

"Two theories may be equivalent in all their empirical consequences yet differ in their ontological commitments."

"Science aims at simplicity and elegance in explanation, not absolute truth."

"What cannot in principle be observed cannot significantly be said to exist."

"Our language mirrors the structure we project onto the world."

"Identity and difference are not absolute relations but depend on the level of analysis."

"The most certain truths are those least subject to empirical revision."

"Philosophy is continuous with science; there is no special philosophical method."

"To understand a sentence is to know under what conditions it is true."

"No statement is immune from revision in light of experience."

"The value of a theory depends on its simplicity and coherence, not just its truth."

"We carve nature at its joints only relative to our conceptual scheme."