Evidential Pluralism and Epistemic Reliability in Political Science: Deciphering Contradictions between Process Tracing Methodologies

Abstract

Evidential pluralism has been used to justify mixed-method research in political science. The combination of methodologies within (qualitative) case study analysis, however, has not received as much attention. This article applies the theory of evidential pluralism to causal inference in the case study method process tracing. I argue that different methodologies for process tracing commit to distinct fundamental theories of causation. I show that, problematically, one methodology may not recognize as genuine knowledge the fundamental claims of the other. By evaluating the epistemic reliability of these fundamental claims, we can find a way out of such conflicts and rescue pluralism.

Triangulation, incommensurability, and conditionalization

“…Having similar cases in mind, some philosophers have recently argued that incommensurability might undermine the value of triangulation. For instance, Runhardt (2021) argued that in some cases, assumptions employed by a theory that supports using a given method might undermine the justification for using another method (supported by another theory). When this is the case, she argued, triangulation seems epistemically useless.…”

“…How should the mere fact that both studies, which rely on entirely different assumptions and employ different conceptual frameworks, support the hypothesis influence the degree of confidence a rational decision maker, whose decision relies on whether the hypothesis is true, assigns to it? Some philosophers, such as Beach and Kaas (2020) and Runhardt (2021), have recently argued that MT has no epistemic value in such cases. We show that their arguments do not apply to the sense of the epistemic value of MT that our account explicates.…”

Some Reflections on Causation

“…Cartwright 2007;Worrall 2010;Northcott 2012;Krauss 2021), while the legitimacy of process tracing in the assessment of causal claims in political science has been hotly debated (e.g. Crasnow 2017;Beach 2021;Runhardt 2021;Dowding 2023).…”

Applying Bradford Hill to assessing causality in systematic reviews: A transparent approach using process tracing

“…31,50,51 As we draw on the principles of process tracing to evaluate a putative causal effect but not its mechanisms, we refer to the causal claims being evaluated as 'hypotheses'. 50,52 A commonly cited example of how process tracing is used to evaluate a general theory is the nuclear taboo hypothesisthat a moral opposition to using nuclear weapons prevented the use of atomic weapons by the United States after 1945. [53][54][55] As this claim is not disaggregated into interlinking parts, process tracing is used to assess the extent to which evidence helps distinguish between the nuclear taboo hypothesis and competing claims, as illustrated in Figure 1.…”