For sentences such as (1), "Columbus knows that the sea is unpredictable", there is a face-value theory, according to which ‘that’-clauses are singular terms denoting propositions. Famously, Prior raised an objection to the theory, but defenders of the face-value theory such as Forbes, King, Künne, Pietroski and Stanley urged that the objection could be met by maintaining that in (1) ‘to know’ designates a complex relation along the lines of being in a state of knowledge having as content. Is the (...) theory safe, then? The aim of this paper is to show that a new problem for the theory arises if we consider attributions of skills, knacks, propensities and abilities. (shrink)