quine home > underdetermination
Underdetermination is a thesis explaining that for any scientifically based theory there will always be at least one rival theory that is also supported by the evidence given, and that that theory can also be logically maintained in the face of any new evidence.
The thinking here began with Pierre Duhem who said, regarding an experiment which provided evidence contrary to a prior belief, "The only thing the experiment teaches us is that among the propositions used to predict the phenomenon and to establish whether it would be produced, there is at least one error; but where this error lies is just what it does not tell us." (Schick, pp 54)
Duhem's view was a step towards fallibilism, the view that any natural observation could be wrong. Quine would take this movement a step further in what he called underdetermination. By this he meant that our lack of certainty about our prior knowledge would allow us to accept multiple theories explaning our current condition.
This is an interpretation of Quine's Nonuniqueness thesis: For any theory, T, and any given body of evidence supporting T, there is at least one rival (i.e., contrary) to T that is as well supported as T.
This is a result of our inability to completely understand or gain access to the whole set of empirical evidence for any one particular situation or system, and therefore our acceptance that new evidence could be made available at any time. This thesis maintains that since there is no method for selecting between our two (or more) valid solutions, the validity of our conclusion is always in question.
Schick, Theodore Jr. Readings in the Philosophy of Science: From Positivism to Postmodernism. Mayfield, 2000.
Laudan, Larry. "Demystifying Underdetermination" in C. Wade Savage, ed. Scientific Theories, vol. 14, Minnesota Studies in the Philosophy of Science, University of Minnesota Press, 1990.