This was the title of a short talk I attended recently. The talk was from a humanities perspective so of course the discussion did not fit within my mental model of the world. But one comment caught my attention which was along the lines of "love is death, as represented by Jesus dying on the cross out of love". This immediately seemed erroneous to me. Jesus dying on the cross has always meant self-sacrifice to me not death. Shortly after Jesus dies he rises from the dead, so the story goes, so his death is not really a death; it is more like a 3-day time-out.
From a biological perspective, love is all about self-sacrifice. Love is one of the main mechanisms our selfish genes have discovered to make us behave altruistically. There are several kinds of love and all motivate selfish-altruism. For instance there is the love shared between friends which is built on a foundation of reciprocal altruism ("I'll scratch your back so you'll scratch mine") and serves to provide the trust needed to create mutually beneficial social structures such as a guard rota so everyone can sleep knowing someone is watching for hungry lions. There is also the love between family members which causes individuals to be altruistic towards family members who are likely to share genes with themselves (hence the genes are being selfish despite the individual being altruistic). Finally there is romantic love which in humans serves a dual purpose of encouraging sex and the production of offspring (genes replicating themselves) and motivate the parents to share the burden of protecting and raising the offspring increasing the chance they will survive to produce the next generation.
Of course there is also the love of abstract concepts which represent a community (eg. nationalism, political alignments) but these are mainly more general forms of the reciprocal altruism or friend-love, where by acting altruistically toward the group the individual expects the group to reciprocate and help them and/or their family.
This theme of love and self-sacrifice can be seen in many forms of media (books, films, TV shows), where love can be both initiated by a moment of self-sacrifice and is the primary motivator for self-sacrificial behaviour. Even seemingly selfish ideas such as revenge for the death of a loved one (popular theme of video games) are from an evolutionary perspective altruistic - evolutionarily speaking it benefits oneself much more to go find a new mate to continue reproducing than to risk one's own life to pursue the murderer - but are still selfish from a gene's perspective - protect the rest of one's family and wider social group (which was historically likely to be genetically related to you) by eliminating the murderer.
The obvious violation to this is homo-romantic love. It is unclear whether homo-romantic love serves an evolutionary purpose by strengthening social ties between more distantly related individuals in a community or by reducing fertility rates to prevent over-population. Or whether it is an biological accident resulting from traits selected for other purposes (eg. friend-love and romantic-love sharing biological mechanisms) or developmental trade-offs (eg. chances of triggering an immune response in the mother vs chances of producing a homosexual child). Research in the area is still on-going but is slow due to the ethical, cultural, and political implications of potential results.
Goodnight and be selfishly-altruistic towards one-another.
