Weller, Cass. “BonJour and Mentalese." Synthese, Vol. 113, No. 2 (November 1997):251-63.
The idea that thinking a thought is producing a string of symbols not intrinsically about anything must initially strike all but those corrupted by philosophy as puzzling in the extreme. I am, of course, not speaking of public systems of symbols that thinkers use when they speak their thoughts, but rather the thoughts themselves. Even if one proposes a linguistic model of thought as silent inner speech, such as the one Plato mentions in the Theaetetus (189e6–190a6) and Sophist (263e3–5), we naturally assume that sentence tokens in Mentalese are unmeant meaners that invest the conventional symbols of spoken and written language with their derivative meaning.