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Why did humans/animals evolve to become self-aware of their own thoughts. That is, why don't humans act and compute like a machine, or walking zombie. In my mind, such creatures would still be as smart and equally capable of surviving, the only difference being they don't experience the phenomenon of self-awareness. (To understand my question think: unconsciously sleep walking)

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What kind of answer are you looking for? If the answer "It is evolutionary advantageous" or "You might not be able to have one without the other" will not work for you, can you give an idea of what you expect? – MCM Jan 16 '13 at 12:15
"such creatures would still be as smart" - if you aren't conscious can you be aware of others' motivations in the same way? Isn't the ability to develop a theory of mind a big part of "being smart"? – Alan Boyd Jan 16 '13 at 13:08
How can you demonstrate that humans are self-aware? How can you demonstrate that computers or worms are not? These are hard philosophical questions not really suited for this site. – terdon Jan 16 '13 at 14:57
@MCM, The answer I personally think is that evolution cannot explain why we have awareness. I posted the question in-case people who know more about evolution could give an explanation. – Mew Jan 16 '13 at 23:39
The thing is that "feeling" something does not demonstrate it as true. Also, it is virtually impossible to demonstrate that animals are or are not self aware. – terdon Jan 17 '13 at 18:48
up vote 3 down vote accepted

There have been many proposals over the years as to why human consciousness has emerged and how, or even what it is.

Most of us will not be surprised to know that there is no consensus about an answer here. Its hard to draw a trend from a single example.

Here is a little survey of the one's I've heard.

  1. We are intelligent because we have opposable thumbs and can use tools, which evolved our brains. This is an old one - maybe as old as Darwin's time. I think its mostly ignored now because so many animals - including pandas and other non primates have opposable thumbs or use tools or both. (monkeys and chimps use tools, and recently crows have also been observed to use tools.)

  2. brain size. We do have a large brain to body size ratio. There are other animals with similar ratios and they don't have internets.

  3. We are 'self-aware'. That is to say we recognize ourselves as an individual. It was proven that other primates can recognize themselves in mirrors (putting a red dot on their forehead. when they see their reflection, they touch their own forehead). So that's not exclusive either. its not a bad idea, but so far it doesn't seem to make the

  4. 'We ate something' I once read a discussion of how humans might have ingested psychotropic plants or fungi. As you can see, this was 2010. Its not the worst idea, but its hard to prove. Lots of experiments on cats since the '60s have not produced cat's who care to tell us if they are intelligent. Maybe they are just too smart in the first place.

These theories, from when I was a student are so discounted now, you can't find too much record of anymore since they were pre-internet and also they seem so unlikely now.

More modern theories have locked onto social configurations of human societies which drive intelligent adaptations. This is stemming from observations that human evolution (the rate at which genetic variants are retained in the gene pool) are accelerating since humans have become social.

These new theories while standing on some amazing evidence are still feeling around in the dark - stuff about how social interactions have created a preference for intelligence-like traits. There is probably something to that - once intelligence gets a toehold it is a clear advantage. But how did it show up only once and why us? I think that's the hard part that science has, for the moment, given a rest.

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Given how we clearly would have no hardship eradicating everything else on earth (though funnily moral objections against doing so), it could be that intelligence/conscience/... is an "absolute advantage" trait similar to, for example, using enzymes rather than ribozymes or DNA in conjunction with RNA - except that we're not yet at the stage where all alternatives are eradicated. – Armatus Jan 21 '13 at 0:56
heh - we're so superior we might end up doing the job on ourselves too! I agree though - nothing seems to be able to stop or trump intelligence... – shigeta Jan 21 '13 at 3:37
@Armatus - Are you sure we could easily eradicate everything else (well, all other life) on earth? Viruses might be a tough game, especially those that live in humans. And extremely small things that replicate often and mutate successfully relatively often may adapt pretty quickly to our efforts to eradicate them (not that it would be easy in the first place). – 5th Jan 22 '13 at 3:13
If only the Obama administration had really listened to the Death Star Petition we'd have a running start at it. Seriously there is an idea that bacteria might have come to earth by hitching a ride on a martian meteorite, so some clearly believe its possible microorgs can survive planetary devastation. (search term: "Panspermia") – shigeta Jan 22 '13 at 4:04
A Death Star might be the way to go if we wanted to include ourselves in the noble quest of extermination, but imagine the horror if some tough bacterium would get a foothold on the death star itself! : ) (As for all alternatives that don't include us humans -- it will be tough to get all the bacteria in intestines, mouth, stomach etc out of there) – 5th Jan 22 '13 at 12:19

I don't think you can ever ask or answer for that matter WHY questions in biology. The only answer there is: because it works. Asking why questions implies that there was a reason, and reason cannot exist alone by itself. Reason is held by someone or something. And reason is something that doesn't exist, it is something we created and use for our own purposes and we cannot attribute it to anything else having one. Now, if you asked "how?", that's an answer biology was created for.

There could have been many outcomes to everything in biology but this is the one that appeared and works. This doesn't mean that it is some sort of theoretical or practically optimum, but the law of this universe is survive long enough to improve if needed.

I know that this is an opinion, but it's as close to the answer that you can get. If someone gives an answer to the WHY question, you could never prove it, or you could find evidence for all the possible reasons. And we can't also tap into the reasons of the universe because our intellect and modes of expression are way lower than the universe has.

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