On The Thesis Of Empirical Equivalence

This thesis makes a detailed analysis of the connotation and basic kinds of empirical equivalence; and it demonstrates the relationship between empirical equivalence and under determination; and it expounds the difficulty that empirical equivalence brings to scientific selection. Then it illuminates the rationality of empirical equivalence and its existing theory defects. And then it raises the attitude that we should take to the science realism when we are facing this difficulty.The first part of this article, it explains the concept of empirical equivalence and its meaning in detail. And then, based on this, it expounds two main theory sources of empirical equivalence. One is Syntactic of Quine, and the other is Semantics of Van Fraassen.After cleared up the empirical equivalent concept and the connotation, the article continued to analyze two types of it: partial empirical equivalence and whole empirical equivalence. There are three ways to support the partial empirical equivalence separately: logical-semantics, Duhem-Quine and enumeration. The article mainly expounds Larry Laudan's and Jarrett Leplin's analysis and critique on partial empirical equivalence. Laudan's and Leplin quote three theses to indicate this point. These are: the variability of the range of the observable (VRO), the need of for auxiliaries in prediction (NAP), and the instability of auxiliary assumptions (IAA). Therefore, the partial empirical equivalence is just transitory. The empirical way will decide finally which theory will be more correct. There are two ways to support the whole empirical equivalence. One way is to give a normal arithmetic mostly from A.Kukla's work. The other way is to construct a empirically equivalence rival from a specific scientific theory offered by Reichenberger,Van Fraassen and Jerry Yoram Wind. Then the article continues the analysis and the evaluation on these two ways.The third part of the article points out that if we can't overthrow the empirical equivalence totally, we can find the theory support for the under determination based on the logic of empirical equivalence. Because if empirical equivalence thesis to be tenable, then these different theories can infer the similar observation evidence logically. We continue to deduce. If these different theories have the similar support of observation evidence, they are epistemic parity. From these we can get the conclusion of under determination. In summary, these arguments about the inner relation of under determination and empirical equivalence state that there are some difficulties in empirically equivalence simply to support under determination. So, the supporters of UDT take the empirically equivalence as the reason simply, and then to expound that the reasonability of UDT thesis is insufficient. Like that, which attitude actually can we take in the relation of evidence and the theory?At the last part, the article states the evaluation of the empirical equivalence rationality based on the front: the coming up of empirical equivalence makes people realize that the observation evidence isn't the only standard of the theory selection, and besides the observation evidence, the scientist can help them to select theory by other non- observation evidence; under determination which inferred from empirical equivalence can't disrupt the reality of scientific theory, actually, it can make the science more successful; on the contrary, empirical equivalence promotes the science realism, and the anti-realists have already criticized the points of empirical equivalence in demonstrable way, that isn't the failure of science realism and can't overthrow the science theory selection way inferred by science realism. And that simply indicates the science realism how to prove his position more effective and more rational based on absorbing the criticism of anti-realism.