Empirical Equivalence and Underdetermination of Theory Choice: a philosophical appraisal and a case study

Abstract

In this thesis I deal with the problem of predictive equivalence between scientific theories as a source of underdetermination of theory choice. In the first chapter I explain the problem in detail and I evaluate the solutions that have been put forward. Especial attention is payed to Laudan and Leplin's influential argument. I claim that even though essentially correct, their solution must be reassessed. Their proposal is not enough as to refute the problem, but it does show that the regular practice of science is such that a solution could eventually be obtained. Laudan and Leplin's solution is not ultimate, but it indicates that the problem of empirical equivalence and underdetermination is more a problem of science than of epistemology. In the second chapter I analyse in detail an actual case of predictive equivalence: Lorentz's ether theory vs. Einstein's special relativity. I evaluate a list of reasons that can be invoked in order to make a choice in this contend and I argue that three of them are justified, objective and rational. Finally, I conclude that the reasons that lead to favor Einstein´s theory over Lorentz´s are an instance of L & L solution of the problem, and that those reasons also show that the reassessment I propose is correct.