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If people either individually or through their governments don't limit their populations,
The natural mechanisms of the environment will.

If the majority of people take to heart the idea of not over reproducing and try to limit the number of children to two then we will have successfully become a consciously self-regulating species. This would/should probably include good estimations for what population, on an updated basis, current technologies can support and according adaptations.

More likely the case is we are just another dumb species that is culled through environmental destruction or infighting within our own species.

Part of the reason i think we will simply be another out of control species is because we have a built in tendancy to see our own individual self and/or family/group as somehow being exclusive of the species as a whole. A paranoid delusion of being special, that the facts that do govern everyone & everything else somehow, magically, don't happen to apply particularly to us.

We facilitate this paranoia through many different psychological categorization mechanisms.

Religion - I am one of God's special [self?] chosen individuals that exists amongst [and usually in contention with] the condemed.

Elitism - I am gifted/special/artistic and am free to be as tempermental as i choose [need to be].

Victimization - I have suffered and therefore 'deserve' in the moral balance of the Universe to be granted special indulgences. Interestingly many religions play into this, 'We are the persecuted fill in the blank [Jews, Christians, Muslims, etc.]'

Tyrannical - I am superior and therefore the logic of the Universe dictates that I impliment my will without any checks or balances upon the Universe and everyone and everything in it.

I don't like to see everyone lose their individuality, but I think they should keep in mind context, that they are part of a larger composition.
Maybe if people see/feel they are being observed and judged by others as to the effects of their actions, it will help curb the most agregiously stupid and inhumane behaviors of people.

I don't want to see us turn into a hive species, but that could become a simple necessity if populations get overly large. I would rather see us take on some gently cohesive quality that makes all reasonable effort to consider others and the communities we live in. With larger governing structures and a good degree of personal freedom withing the bigger framework. Adding to that the ability to effect collective violence if necessary to defend our home.
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