Abstract
According to sentimental perceptualism, affect grounds evaluative or normative knowledge in a similar way to the way perception grounds much of descriptive knowledge. In this paper, we present a novel challenge to sentimental perceptualism. At the centre of the challenge is the assumption that if affect is to ground knowledge in the same way as perception does, it should have a function to accurately represent evaluative properties, and if it has that function, it should also have it in its future-directed imaginative use. As the data on affective forecasting errors indicates, however, the affect system does not have that function. As a result, it is doubtful if affect can do the kind of knowledge-grounding work that sentimental perceptualism assumes it does.