1. The issue - The reflection I am proposing was stimulated by some recent research on the mental processing of proper names. However, the issue I am raising is independent of both the particular nature of such results and the fact that they are accepted as well established. The question I would like to ask is whether (neuro)psychoIogicaI results on the mental processing of language can falsify (or confirm) semantic theses about natural language. By a semantic thesis I mean something like any of the following: that proper names are rigid deslgnators, that the meaning of natural kind and natural substance nouns has an lndexical component, that sentences of the form ‘AII Ps are Qs’ have a conditional structure, and so forth — the kind of theses that are usually discussed in philosophy of language. I am not regarding these particular theses as sacrosanct: I am not implying that it would be a scandal for reason if they were contradicted by psychological data. I just wonder whether neuropsychological results have any role to play in the discussion of such theses, or whether they are altogether out of place, for reasons of principle. lf the theses I mentioned are regarded as philosophical as opposed to Ilnguistlc, then the issue of continuity vs. separation of science and philosophy ls involved. One way of holding that philosophy ls continuous with science consists ln holding that scientific results can occur as premises ln philosophical arguments} lf, against Qulne, one denies that this could ever legitimately be the case, then our issue ls settled. lf on the other hand one admits that, in principle, there is nothing wrong with appealing to scientific results ln philosophical arguments, it can still be wrong to appeal to this particular kind of results to prove or disprove that particular kind of philosophical theses. However, it won’t be wrong for reasons of principle, involving the nature of the philosophical as opposed to the scientific enterprise; it will be for reasons that are peculiar to these particular results and philosophical theses...