Human being emulator + open source development =
We could all be a little more like
Saige and
Pseudo_Intellectual, instead of just wishing we were.
We could fix what's wrong with
annoying noder's name here
Seriously, though, I'd use an argument analogous to the one
Eric Drexler uses for the
feasibility of
nanotech (and heavier than air flight). "It's already been around for years."
In other words, the people who believed that heavier than air
flying machines could not be built were
wrong from the very start, because
birds are heavier than air flying machines. People who believe that
nanomachines cannot be built are wrong from the very start because
ribosomes and
viruses
are nanomachines. Likewise, the existance of natural intelligence presents the strongest argument for the feasibility of AI (and from there, NI->AI
uploads).