I think the proponent argument would be more as follows:
1. The brain seems important to consciousness, yet there is a variety of evidence suggestive that it might not be the cause*.
2.
Separating correlation from causation, as well as
icons from actualities, is difficult. As such it becomes difficult to determine whether the brain is a consciousness producer,
localization of Universal Idealist Mind, or filter/transmitter
given most if not all evidence from neuroscience can be interpreted each way. So we need to go deeper:
3. For the brain, as defined by materialism, to be producer of subjective experience
requires the miracle of emergence. Besides the requirement of a "something from nothing" miracle there are other reasons to doubt a materialist explanation relating to the nature of subjective experience.*
4. Evidence for observer-participancy (
here +
here) suggests consciousness has efficacy outside of your skull, though any certainty about this remains an open question. For example,
Kauffman's poised realm explanation for consciousness may suffice.
5. The way out of inclusion of an ex nihilo type miracle in which nonconscious matter becomes conscious is to appeal to some kind of "proto-consciousness". In refuting Dennet the
anthropologist Graeber suggests panpsychism, and it leads us into territories adherents to materialist evangelism* would likely want to avoid. Why would you only have "proto-consciousness" in a particle? What stops a particle from being fully aware & directing bodies via quantum superposition,
as Grof (AFAICTell) suggests? Yet if you're wandering into these landscapes, you aren't that far from
Hammeroff's notion of a quantum soul.
So it seems to me that even if one takes the materialist position at the outset it doesn't matter much. You can still end up with ideas conducive to immortal conscious entities, at least at this point & time in our history.
*
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