 Contemporary proponents of LOTH endorse RTT+COMP. Historical proponents also believed something in the vicinity (Normore 1990, 2009; Panaccio 1999 [2017]), although of course they did not use modern terminology to formulate their views. We may regard RTT+COMP as a minimalist formulation of LOTH, bearing in mind that many philosophers have used the phrase “language of thought hypothesis” to denote one of the stronger theses discussed below. As befits a minimalist formulation, RTT+COMP leaves unresolved numerous questions about the nature, structure, and psychological role of Mentalese expressions.