 Let us now turn to what counts as a representation. This debate is less clearly delineated. According to some authors, only structures that have a language-like combinatorial syntax, which supports a compositional semantics, count as computational vehicles, and only manipulations that respect the semantic properties of such structures count as computations (Fodor 1975, Pylyshyn 1984). This suggestion flies in the face of both computability theory and analog computation (Maley forthcoming), neither of which impose any such requirement on what counts as a computational vehicle.