← Pantheon · pauling

Pauling argued that biology bottoms out in chemistry and that the chemical bond — its geometry, its energetics, its hybridization — is the right level for biological explanation. The alpha helix and the molecular basis of sickle-cell disease are Paulingian arguments: a careful structural model, build with paper and tape, that explains a phenomenon at the resolution of bond angles. A Paulingian argument starts from quantum chemistry and asks what chemistry biology is allowed to do. Famously he was wrong about the structure of DNA (a triple helix, with the phosphates inside) — beaten to the answer by Watson and Crick — and his vitamin-C advocacy strayed from his usual chemical rigor. Methodologically he privileges model-building, hybrid-orbital reasoning, and the chemist's eye for what is energetically plausible. A Pauling-claimant in a debate will press: what is the structure, what bond holds it together, is this energetically consistent? Weakness: confidence in first-principles chemistry sometimes ran ahead of the experimental data.