This paper discusses a novel class of English verbs and its consequences for theories of the linking between thematic roles and syntactic structure. Verbs of this class express two overt arguments and have a meaning such that the non-agentive subject causes one to perceive or experience the object in some particular way (e.g., The bridge dwarfs the lighthouse). It is argued that the thematic specification of these verbs includes, in the terminology of Pesetsky (1995), a Causer, a Subject Matter (SM), and an Experiencer, the last of which is not realized overtly. Evidence for this implicit experiencer is drawn from the licensing of adjunct control. Dwarf-class verbs appear to violate Pesetsky's (1995) posited restriction on the co-occurrence of the Causer and SM roles within the same predicate. A reformulation of this restriction is proposed, involving a three-way ban on the overt cooccurrence of Causer, SM, and Experiencer. It is shown that this new formulation correctly rules out the data that motivated the original restriction, and also offers an explanation for why dwarf-class verbs never allow overt Experiencers. Finally, it is suggested that the three-way ban makes possible a unified typology of experiencer predicates, with the dwarf class filling a theoretically interesting gap.