Though the original developer of the language of thought hypothesis is Jerry Fodor (Fodor, 1975), many factors before him helped put it in place. One of them, falling outside philosophy, is the theory of computation developed by Turing and realized in digital computers. This gives us a general picture of processing symbols according to algorithms, a picture that morphs easily into one of mental processes as computations over semantically contentful representations. And that provides a major piece of Fodor's language of thought hypothesis.