Experimental Equality and Underdetermination

During this century,there emerged from the philosophical analysis of scientific theories two results invested with broad epistemological significance.In the second chapter we studied two different and at the same time interrelated issues.First, we studied ontological status of molecular structure and then we studied its epistemological status. In the third part a contemporary biologist reading this might well conclude that essentialists had no scientifically respectable way of understanding the existence of variation in nature.At the forth chapter representing and Intervening concluded with an experimental argument for scientific realism about entities that cannot in any literal sense be observed. It was based on the fact that we regularly use such entities to investigate other parts of nature, and that we reliably build apparatus to take advantage of some of the causal properties of such entities.In the end chapter It was based on the fact that we regularly use such entities to investigate other parts of nature.and that we reliably build appar¬atus to take advantage of some of the causal prop¬erties of such entities.