I am writing a thesis on the possibility of machine consciousness (e.g., the possibility of creating a silicon-based system that has subjective, qualitative experiences in the same way we take ourselves to have them). In my informal (and very limited) polling, it seems that many philosophers are sympathetic to the project.
However, not all functions can be realized by all structures (e.g., you can’t make a car out of paper towels). Given the many fundamental asymmetries in structure between humans and silicon-based systems, it is at least plausible that human consciousness cannot be realized in silicon-based structures.
Of course, proponents of machine consciousness will reply that the properties relevant to consciousness are multiply realizable, but do they have any evidence?
I was wondering what others take to be the strongest arguments either for or against the possibility of machine consciousness. What is the strongest reason to think human consciousness is realizable in silicon? And what is the strongest reason to think it is not? Centrally, what aspect(s) of a putative realizer seem most relevant to realizing human-like consciousness?