Descartes' Error: Emotion, Reason, and the Human Brain

Damasio's central discovery is that patients with damage to the emotional centres of the brain do not become more rational — they become unable to decide at all. Emotion is not noise in the decision-making process; it is the infrastructure. This demolishes the Cartesian separation of reason and feeling that still haunts most organisational thinking about "data-driven decisions." The somatic marker hypothesis — that the body marks options with emotional valence before conscious deliberation begins — reframes how we should think about user experience and choice architecture. For anyone building products that help people choose, this is essential reading.