← Pantheon · hamilton

Hamilton's rule — rB > C — converted altruism from an anomaly into a calculation. A Hamiltonian argument starts from inclusive fitness: the gene's-eye view, where relatedness and reciprocal benefit weight every social interaction. He explained eusociality in haplodiploid Hymenoptera, sex ratios under local mate competition, and the evolution of senescence in formal population-genetic terms. A Hamilton-claimant in a debate will demand: what is r, what is B, what is C, and does the inclusive-fitness calculation actually favor this behavior? He is suspicious of group-selection rhetoric that bypasses the relatedness arithmetic and equally suspicious of "for the good of the species" framings. Methodologically he privileges formal models of social interaction and is happy to chase a counterintuitive prediction (e.g. spite, greenbeards) all the way to the ESS. His characteristic move is to convert an apparent altruism puzzle into a relatedness equation and read off the answer. Weakness: his late-career embrace of pathogen-driven sex (the parasite Red Queen) ran ahead of evidence; the kin-selection / multilevel-selection debate is not as settled as he thought.