And what does denial of death have to do with instincts? We have no information on 'exposure to death', because "One does not simply die to acquire data on death". It is this lack of information that is common, therefore the conclusions are derived from the same basic premises.
Well, you make me more or less repeat myself, so it's boredom multiplied by two now, but to me the omnipresent
need to explain the unknown every human has is blatantly one of the most basic instincts we have. Actually it's a mix of two instincts, imo. The first one is called curiosity, and is the spark that led human evolution and history. You'll notice how the more evolved an animal is, the more curious it is about his surroundings, and the more inclined to explore them it is. In the case of humans, capable of abstract thought, there's a whole new, endless world of pure intellect to explore. The second one is called fear: fear of the unknown. Humans instinctively fear what they don't know/understand just like they instinctively fear the dark: because in the unknown might reside dangers. What is more unknown than the concept of non-existence, especially as it is tied to the very realization of our most scary inner, instinctive fear of death?
If it weren't for these instincts, there would have been little
need to find explanations that actually
deny death. Some people could have come up with those, but at least as much people (and probably the vast majority) would just have gotten to the simpler, logical conclusion death is death: it happens, as shit does.
As they
all felt compelled to find an acceptable explanation for something they didn't understand, they all came to the same conclusion, that death doesn't exist. You may use afterlife, you may use reincarnation, or you may use new age bs that's pretty much FF7's lifestream to idealize how your soul will keep living inside the grand scheme of the biosphere or in an actual embodiment of the living world called Gaia, all these differences are purely cosmetic. All tell you there is a
soul that carries on, so you don't die, even if in concept only. Doing so, most of them also flatter your pride suggesting that you are more than just a bunch of meat that happens to be able to think by a lucky variable in evolution.
Only today we have some atheists that try to admit that it's just illogical and silly to think there has to be
something only because we are too ignorant to conceptualize what nothingness is. And even between them I wonder how many are really comfortable with that deep down and how many are just diverting their eyes and looking at science in a religious way waiting for it to give them an equally acceptable answer about that. How
evolution is often simplified in popular culture into something that closely resembles
becoming a superior being is a bad symptom.
It's not like I care about any church. But if you are unaware, Scientology basically was created by a failure of a science fiction novelist
.
I know. The difference is the novelist behind Christianity was more successful. How he pulled it off I really don't know... I mean, imaginary friends, women born of ribs, talking snakes, gods playing pranks at you (sacrifice your son to me! / Ok... / trololololo you fell for it!) and putting around "don't press me" red buttons... I mean, come on, it's not even good fantasy, this God character is too whimsical to be taken seriously!

Well, I have never read the novels written by that Hubbard guy (that I remember of, at least), but they can't have been
that bad.
Scratch that, just checked on wiki: I must have read at least two of his novels when I was a kid. And I don't remember a single word of them. So yep, the B-Book must have had to be better somehow. Probably comedic value, I guess. All those things about philistines and their foreskins... yep, it was pretty funny. And gross. Troma might have been behind the original concept.
FYI: You conclude instincts do not change, but you are agreeing with a point stating that it does
.
Nope, you misunderstood me. I just stated how the mind can redirect them. The instinct still is very simple: "I want to fuck and impregnate the woman that is the best possible mate to grant me an healthy offspring and its correct upbringing" (man, I feel such a douchebag... is it just me? I want to believe I can still love; ponies, maybe, not women, but still!

). It never changes and it never can be elaborate, it can only be an impulse. The instinct doesn't even know what a "woman" is, even such a basic factor is understood only by our perception.
The perception of what is the best possible mate is what can change as the environmental conditions change. And even cultural imprinting, that pervasive imprinting that can leak into the subconscious too, can change that perception: that's how a body build that by logic would probably still not be the best one even in the current environmental conditions might appear to be so.
I'm not sure it's called
rabbit therapy in English too, but the idea is pretty simple: take a rabbit, give it food, but anytime he gets near it electrocute the poor bastard. Soon enough two things will happen:
1 - each time it sees food it will become scared like hell;
2 - it will stop eating. As it has learnt that trying to eat brings pain (and pain means danger of death) his instincts are led to believe that on balance trying to eat is a more imminent danger than not eating at all. And it will starve to death.
The instincts haven't changed in the slightest, but its perception was twisted so much that the very survival instinct lead it to an inevitable death.
I know, it's an horrible practice, but believe me:
The asshole had it coming

The only way such instincts could change is through long evolution. Let's say (silly sci-fi, there's no way an artificial custom such as this could remain unchanged for hundreds of generations) we begin reproducing only in vitro. That's a pretty efficient way to ensure we have the healthiest possible offspring. And we do that for a looooooong time. It is safe to assume the reproductive instinct - as we know it - might slowly dull, as it isn't needed as much anymore, and individuals who don't waste too much energy on it have the same chances of "mating" than anyone else, thus in the genepool the factor "reproductive instinct" gets slowly "watered down" as it isn't anymore a trait favored by species selection.
We would slowly be less and less attracted to the opposite sex, up to the point we could completely forget the meaning of sex. Then the whole in vitro fertilization system crumbles down. Would we immediately revert to feel that same instinctive urge with the same strength we do now just because suddenly it is needed again? I'd say no, it would once again take a while, as it would need to be sharpened once again: those few that still have it sharper than others would be more successful at mating, and evolution would slowly find a new balance.
Know what? The rest of the responses are messes beyond sorting through. I'm better off having Kind Arthur chop your house down with an axe while singing the trololololololololo l song.
The whole topic can be tl;dr; to this: It's magic, I ain't gotta explain shit!

And I try once again to make everything slide into something maybe less self-flattering than verbal diarrhea, but surely more fulfilling: boobs.