Stephen Yablo offers a solution to the problem of mental causation by claiming that the physical is a determinate of the mental's determinable, and therefore the mental and physical do not compete for causal relevance. I present Yablo's solution and argue that the mental‐physical relation cannot meet three necessary conditions for determination. That relation fails to meet the requirements that determinates of the same determinable be incompatible and that no property can be a determinate of more than one determinable. Further, (...) the mental and physical do not fall under the same series of scope inclusions as determinables and their determinates must. Yablo's conception of determination might be rendered more general to avoid these objections, but doing so would prevent it from functioning as a competitor to extant theories of the mental‐physical relation. Thus, Yablo's solution to the problem of mental causation cannot be both adequately specific and correct. (shrink)