Global Skepticism and Brains in a Vat

This is certainly nothing like a conclusive refutation of skepticism. To argue against skepticism we must accept something to argue from. The skeptic may then 

There are two issues here which should be carefully distinguished. The first is how fallibilism stands with respect to two claims. The second is which of these claims represents skepticism. The two claims are the following  

To make sense of this assumption, consider the following situation. There is a computer which runs a program producing English sentences. Let us call it ESD, which stands for English speaking device. ESD knows the whole grammar of 

Another consideration which suggests that (B) is more fundamental than (A) is that it helps to clarify why the connection must be of the right sort. The hook-up to electricity is not the right sort because it does not involve epistemic access. 

Once we accept that the plausibility of (A) derives from (B), it becomes clear that the assumption is very much in the spirit of internal realism. Internal realism regards reference is an epistemically loaded notion, since it argues that it is fixed by justification conditions. Metaphysical realism, on the other hand, treats reference as non-epistemic. If it did not, it would have to deny (MR2), the thesis that truth is radically non-epistemic. Since truth is determined by reference, were reference epistemic, truth would become epistemically tainted. 

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