This article advances the conditional incompatibility thesis, which when left unaddressed, poses challenges to the pragmatic maxim as a guiding framework for mixed methods research. The conditional incompatibility thesis stands in opposition to two claims, the first pertaining to the position that incompatibility can be avoided by adherence to a "whatever-works" maxim. Also questioned is the claim that quantitative and qualitative data are inherently incompatible. Arguing that there are conditions under which incompatibility occurs, we illustrate within the context of latent variable modeling how particular techniques, methods, and/or decisions fail to be philosophically neutral. Offered are methods through which researchers can be more mindful of, and thus transparent about, the influence of philosophical perspectives in their work.