The Selfish Gene (and Memes)
Richard Dawkins · 1976
"The gene, not the organism, is the true unit of natural selection — animals are 'survival machines' built by genes to replicate themselves, and culture spreads by an analogous unit Dawkins named the meme."
Dawkins reframes the unit of evolution: not the individual animal, but the gene. Genes that happened to code for traits improving their own copying survived differentially across deep time; from this angle, an animal's body, brain, and behavior are a 'vehicle' built by genes for the purpose of replicating themselves. Calling genes 'selfish' isn't a claim about intention — genes are molecules with no intentions — it's shorthand for a logical property: we only observe the genes whose effects helped them get copied, because the alternative ones simply aren't here anymore.
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Leviathan
"Without a common power to keep everyone in check, human life would be a war of all against all — so rational self-interested individuals agree to surrender some of their freedom to an absolute sovereign in exchange for security and order, and that agreement, not divine right, is the true basis of political authority."