Full Idea
Central state identity theorists had trouble providing for the nomological possibility of rational machines (and hence no space for a non-biological, e.g. computational, theory of intelligence).
Clarification
'Nomological' means concerned with rule-following
Gist of Idea
If mind is just physical, how can it follow the rules required for intelligent thought?
Source
Jerry A. Fodor (Psychosemantics [1987], p. 67)
Book Reference
Fodor,Jerry A.: 'Psychosemantics' [MIT 1993], p.67
A Reaction
I surmise that a more externalist account of the physical mind might do the trick, by explaining intelligence in terms of an evolved relationship between brain and environment.