Quine also notes that deviant logics usually lack the simplicity of classic logic, and are not so fruitful.
Quine even believed that logic and mathematics can also be revised in light of experience, and presented quantum logic as evidence for this.
Years later he retracted this position; in his book Philosophy of Logic, he said that to revise logic would be essentially "changing the subject." In classic logic, connectives are defined according to truth values.
This principle presupposes that between multiple theories explaining the same phenomenon, the simplest theory—in this case, the one that is least dependent on continual ad hoc modification, is to be preferred.
As popular as the Duhem–Quine thesis may be in philosophy of science, in reality Pierre Duhem and Willard Van Orman Quine stated very different theses.
Duhem believed that only in the field of physics can a single individual hypothesis not be isolated for testing.
He says in no uncertain terms that experimental theory in physics is not the same as in fields like physiology and certain branches of chemistry.Following the Duhem–Quine thesis, Norwood Russell Hanson developed the concept of "theory-ladenness" of observation; observation does not constitute neutral, objective data, but a theory dependent interpreted knowledge.Together with Thomas Kuhn's argument for the existence of the socio-historical dimension in scientific knowledge, the Duhem–Quine thesis made a significant contribution to the philosophy of science and theory of knowledge.However, it was eventually accepted that an unknown planet was affecting the path of Uranus, and that the hypothesis that there are seven planets in our solar system was rejected. a theory and its background assumptions) as a whole can be tested against the empirical world and be falsified if it fails the test, the Duhem–Quine thesis says it is impossible to isolate a single hypothesis in the bundle.Le Verrier calculated the approximate position of the interfering planet and its existence was confirmed in 1846. One solution to the dilemma thus facing scientists is that when we have rational reasons to accept the background assumptions as true (e.g.The connectives in a multi-valued logic, however, have a different meaning than those of classic logic.As for quantum logic, it is not even a logic based on truth values, so the logical connectives lose the original meaning of classic logic.The hypothesis in question is by itself incapable of making predictions.Instead, the consequences of the hypothesis typically rest on background assumptions from which to derive predictions.Their theses also blurred the sharp distinction between theories in the natural sciences and those in the social and human sciences, distinctions that had been in question under hermeneutics.The Duhem–Quine thesis (also called the Duhem–Quine problem) states that it is impossible to test a scientific hypothesis in isolation, because an empirical test of the hypothesis requires one or more background assumptions (also called auxiliary assumptions or auxiliary hypotheses).