His studies have concerned themselves with the idea of whether thought is expressed in language or whether it is absurd to think so. Fodor also attempted to tie in the design of the brain to the thoughts held within. This is described by many as a return to the 19th century practice of phrenology, although Fodor offers more science to back his version up than phrenologists. It is these views which led other philosophers, such as Jared Cole and Daniel Dennett to describe Fodor's claims as absurd and out of date.