Even after you can feed and fend for yourself, you’re still chronically self-deficient. Darwin said any species that could “profit by living in society” would evolve social instincts. “Individuals which took the greatest pleasure in society would best escape various dangers; whilst those that … lived solitary would perish in greater numbers.” And any human without a “trace of such feelings” was “an unnatural monster.” We’re likely the social-est species ever and evolved to chronically crave company. - http://bigthink.com/errors-we-live-by/you-are-by-nature-self-deficient