The Grounds of a Critique of Pure Reason

For the realist metaphysician, certain notions in metaphysics are objectively theory-guiding. But what makes them so? Echoing others, Dasgupta (Citation2018) suggests that the realist metaphysician faces trenchant difficulties here—resulting in the problem of missing value. I first propose that Kant's project of a critique of pure reason faces this problem: he supposes that the notion of ground is objectively theory-guiding in metaphysics. This investigation reconstructs his response. I argue that, for Kant, a notion is objectively theory-guiding in metaphysics if (and because) it is required for the successful exercise of reason. By analysing the requirements on undertaking a critique of pure reason, we will see why his notion of ground would be objectively theory-guiding in this sense. I conclude that his response generalizes to yield a potentially promising response to the problem of missing value.