Chomsky is a fairly wordy fellow, so it is difficult to paraphrase his thoughts in 90 words. Here goes. Chomsky argues that there really is no such thing as a concept for the "body", that is, we can observe it, measure it, characterize it, but we cannot define the body as a concept for philosophy. Therefore it is quite difficult for us to draw a distinction between the body and those things we might call phenomena - independent thought, reason, the soul, etc. - so it is impossible from a logical standpoint, according to Chomsky, to create theories which attempt to explain these phenomena because we have no body concept as a starting point. We have only popular, social and religious beliefs, none of which are based in logical philosophy.
Simply put, what Chomsky means to say when speaking of “Mind-body dualism” is the fact that Empiricism,gazes upon the study of the body as a natural science,and that it has in some ways embraced Dualism, the philosophical theory based on the idea of opposing concepts, especially the theory that human beings are made up of two independent constituents, the body and the mind or soul,that which is undoubtedly, in no way natural and as such is clearly going against its original doctrine;as such he finds it very hard to accept thereby recognizing it as nonesense.
He goes on to say that Empiricism also states that “the brain is a tabula rasa, empty, unstructured, uniform at least as far as cognitive structure is concerned.” Chomsky states that he has no reason to believe this and that to him there isn’t any way of disproving the fact that ones pinkie could be the bodies most complex organ. By use of this example he
wishes to convey that there is no reason to believe that the higher mental division isn’t connected to the pinkie,which represents the seemingly smallest organ, per se.