Besides justifying the transfer of wealth to kleptocrats, institutionalized religion brings two other important benefits to centralized societies. First, shared ideology or religion helps solve the problem of how unrelated individuals are able to live together without killing each other — by providing them with a bond not based on kinship. Second, it gives people a motive, other than genetic self-interest, for sacrificing their lives on behalf of others.

Jared Diamond (b. 1937) American geographer, historian, ornithologist, author

Guns, Germs, and Steel, ch. 14 (1997)
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