Craig,
So what is "consciousness"? It also exists (and we are individually proof of that fact). Can our personal "consciousness" cease to exist?
A complex subject, and one we can get nowhere near examining in detail here, but the problem that seems to me to exist with "consciousness" and its possible existence beyond our deaths is that consciousness, unlike matter, depends on experience.
Perhaps the term "consciousness", which the Koine Greek describes as "inside knowledge", could be defined as "experience *of* experience*. It relies on sensation and experience to exist, without sensation, there is no consciousness. It seems to be that if a person accepts that definition of consciousness, it cannot exist without sensation, thus when sensation ceases, so does consciousness.
I read a very interesting book a couple of years ago, which in some ways attempts at least to deal with such questions. It was written by Lelsie DeWart and is entitled, "Evolution and Consciousness - The Role Of Speech In The Origin and development of Human Nature". Drop me you address by PM and I will send it to you.
Best regards - HS