The philosophical view known as Epistemic Structural Realism appeals to the concept of ‘structure’ in order to defend a version of Scientific Realism that nevertheless respects historical considerations of ontological discontinuity between successive scientific theories. It seems that the structures of some scientific theories are only continuous with the structures of successor theories when the former are characterized as nomologically impossible idealizations of the latter, since this continuity involves allowing some quantity in the formal structure of the successor theory to tend towards some physically unrealizable limit. But if this is the case, then the earlier theory cannot be physically realized. It is thus unclear in what sense the structure of the earlier theory can be said to accurately represent the physical structure of the world, since the former structure is nomologically impossible. If the nomological impossibility of the earlier theory’s structure undermines the Scientific Realist’s justification for believing in it, moreover, then the preservation of structure through theory change will fail to secure justification for the belief in the accuracy of the successor theory’s formal structure. The Scientific Realist will thus be left with no reason to believe in the structural accuracy of current scientific theories.
"The Problem of Nomological Impossibility for Epistemic Structural Realism,"
The Hilltop Review: Vol. 7
, Article 11.
Available at: http://scholarworks.wmich.edu/hilltopreview/vol7/iss2/11