Concrete Propositions: An Argument from Internalism to Psychologism

Anthony Newman

Internalism about propositional-attitude contents ("propositions") is the view that having any particular belief, desire, (etc.) is an intrinsic property. In this paper I argue that reasonable internalists should also believe the crazy-sounding view I call "concretism" -- namely, that propositions are concrete entities. If both concretism and internalism are true then propositions are concrete entities in the head, which sounds a lot like the "psychologism" famously attacked by Frege and the later Wittgenstein. So the upshot of my thesis is that psychologism is just as reasonable as internalism.

I argue this by showing that the central premises of the two classic arguments for internalism can also be used to form two arguments for concretism. First I present the classic arguments for internalism: one says that if bearings of attitudes toward propositions were extrinsic properties then they could not figure in causal explanations of behavior in the way they seem to; and the second says that if bearings of attitudes toward propositions were extrinsic we could not know our own attitudes in the way we seem to. Then I use mostly the same premises in two arguments for concretism: the first says that if propositions were abstract they could not figure properly in causal explanations of behavior; and the second says that if propositions were abstract we could not adequately know our own attitudes.

Finally I examine those premises in the arguments for concretism which did not explicitly appear in the arguments for internalism, and I suggest that the internalist is committed to them as well. My conclusion is that the only thing separating internalism from psychologism is "Methodological Nominalism", the intuitively plausible idea that contingent facts about abstract entities hold only in virtue of facts about what is concrete.