On The Path Of Non-fully Decisive Defense

The basic content of Underdetermination Thesis is that for any theory (T), there is an empirical equivalent but logically unequivalent theory (T’). Referring to the scope of theory and the sense of empirical equivalence, the justification of Underdetermination Thesis can be divided into weak and strong sense. Laodan&Leplin’s arguments of the instability of auxiliaries gave a strong strike on the justification of Underdetermination Thesis. The supporters of Underdetermination have to response to this challenge in different strategies. These who support Strong Underdetermination of Theory failed to give a mechanism which could produce an empirical equivalent rival for any theory. They mainly turn to the total theory strategy which has its own difficulties; others choose to defend the thesis in weaker empirical equivalent strategies. Comparing with problems of Underdetermination of Total Theory, weak Underdetermination of theories and Underdetermination of local theories might be much more promising strategies.