As we're talking about social sustainability: to succeed in even small groups we work together as a team... no one man can, for example, make a computer. One man doesn't know how to process the sand, how to make a processor, and on top of all that create high-level programs with good UI. Ligltly implicit within team work is good human relationships... it sort of goes hand-in-hand I think.
Killing people, depriving them of freedom, etc. all strain humans' happiness and survivability.
If you are interested in exploring this in greater detail, I highly recommend giving Sam Harris' book, _The Moral Landscape: How Science Can Determine Human Values_, a read: http://www.amazon.com/Moral-Landscape-Science-Determine-Valu...
As an example I offer http://www.amazon.com/The-Moral-Landscape-Science-Determine/... by Sam Harris. Absolutely none of his moral claims make any sense without first accepting parts of his moral view that he fails to even question. In fact he uses an unquantified quantity called "well being" as justification for his theory. Yet the only scientifically supported definition for well being for living things is "evolutionarily successful". And by that measure, being religious and scientifically ignorant is very good for you!
Yet his reasoning is utterly compelling to himself, Richard Dawkins, and many other "skeptics".
Harris, who has trained both as a philosopher and a neuroscientist, argues against the popular notion that science can have little or nothing to say about morality. Necessarily, he confronts related ideas like moral questions having no objectively right answer and science and religion being "nonoverlapping magisteria". Basically, he says that all moral questions must relate to maximizing the wellbeing of conscious creatures, and that what increases or decreases a creature's wellbeing can be studied scientifically at the level of the brain.
I just started reading it. Even if I'm not yet sure that I'm going to be completely convinced of the claim that "science can determine human values," I'm finding Harris to be a very clear thinker, as well as an amusing writer.
If you want a taste of his ideas and style, you can watch his TED talk, "Science can answer moral questions."
(It isn't available from Amazon until October 5; I bought my copy in a bookstore.)
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