Scientific Realism and Theory Comparison in the Face of Disciplinary Diversity: Why Go Local?

Abstract This paper offers an abstract characterization of the scientific realism debate (SRD) as a dialectical process of formulating, testing, and refining epistemic principles, and argues that it inherently involves a comparative methodology: the justification of realist or antirealist stances hinges on identifying epistemically relevant similarities and differences among theories—potentially from different disciplines or eras—within “segments” of science that exhibit optimism- or pessimism-inducing track records. Growing critiques of SRD advocate a “localist” turn, contending that disciplinary diversity undermines the feasibility of “global” principles and theory comparison, thereby necessitating a case-by-case approach. However, I argue that disciplinary diversity alone cannot mandate localism without appealing to particularism— a disputed meta-epistemological thesis that denies the normative force of principles altogether. Demonstrating that the viability of localism depends on particularism is far from trivial, since, as I show, localists themselves often overlook this dependence. Moreover, even when particularism is (apparently) endorsed, its radical implications seem underappreciated. To clarify what is at stake, I introduce a reason-based “weighing” framework for normativity, contrast particularism with two forms of generalism , and examine their consequences for the “localism–globalism” debate and the role of comparative methods in SRD. I conclude that embracing localism requires more demanding philosophical commitments than is commonly acknowledged. The apparent ease of “going local” in response to manifest disciplinary diversity is significantly overstated.