Why materialists are predominantly materialists

[Neo-Scholastic]

Are you saying that with a sufficiently advanced technology, one person could actually manipulate a second person's brain and as a result experience what the second person feels? If so then you are just supporting your point with wild speculation and issuing promissory notes. Bennyboy isn't making an argument from ignorance. He is simply pointing out that you have no evidence to support your theory.

By saying that we cannot see what you're experiencing, benny is making a claim about what is possible.  No I don't know for sure that it is possible, but likewise he doesn't know for sure that it isn't possible.  Yet here he is making the claim.  

Fair enough. People should generally avoid stating that something is impossible, particularly with respect to technology. I think bennyboy's positive claim is similar to saying that the PNC always applies. The notion that a given mental property is identical in all ways to a specific brain state clearly violates the Law of Identity. It's not a matter of someday, maybe finding a way to bridge that divide. A knowing subject has privileged access to experiences not available to any objective observer, not even in principle. A cascade of neural activity may have the same efficient cause, like a poke, as the associated sensation but that does not mean the sensation are the same thing as the neural cascade. It's like saying that the material of a column (stone) is the same as its form (Doric).