Well, you can kill a mind without killing the brain, so...
> Does Man have a dual nature?
Umm... sure. What the hell.
Iggy: If one nature of Man is the physical body, what is the other nature?
>What is the source of the survival instinct?
Basic evolution. Those without a survival instinct don;t survive.
Iggy: Doesn't your anwswer presuppose a survival instinct as a priori? knowledge?
> Another possibility is that God does exist.
And another is that Allah exists. And another is that Azathoth exists. And another is that the universe was sneezed out the nose of the Great Green Arkleseizure. And another is that we're all in The Matrix. Lots of possibilities. One must be reasonable, however.
Iggy: You must have inadvertently overlooked this part of my question: Rationalization is a reasoning process; according to those who deny the existence of God, spiritualty is not reasonable.
> Empirical evidence that one has had a spirtual experience might be a change in behavior after said experience.
Oh, you mean like going nuts after overdosing on acid? Craving cigarrettes after smoking? Beating the crap out of a guy after finding him nailing your wife, and then no longer treating her kindly? Ceasing to vote Democratic after getting mugged?
Iggy: Those would not be typical of the behavior changes noted as evidence of a spiritual experience (except maybe the LSD one and the voting Democrat one, lol). You have, however, missed one you should try to nail me with: "You mean like killing infidels with an airplane?"
> If one nature of Man is the physical body, what is the other nature?
Nintendo. No, wait... PlayStation. XBox?
> Doesn't your anwswer presuppose a survival instinct as a priori?
Nope. Put two critters together. If one does stuff that leads it to survive, and the other does stuff that doesn't lead it to survive, then a "survival instinct" can be implied.
> You must have inadvertently overlooked this part of my question: Rationalization is a reasoning process; according to those who deny the existence of God, spiritualty is not reasonable.
That ain't a question.
> You have, however, missed one you should try to nail me with: "You mean like killing infidels with an airplane?"
Well, yes, being converted into carbon dioxide, water vapor and ash can be considered a change in behavior. Unless, of course, that's something you do on a regular basis anyway...