The longevity spreadsheet that fit on one screen

He had a wearable, a sensor, an annual private health check, a quarterly blood panel, and a folder of PDFs that nobody had ever read end-to-end, including him. He had started taking the PDFs to dinner parties as a joke. He was not joking. Underneath the joke was the suspicion that he had built a personal data set in order to avoid making any decision with it.

He shrank the spreadsheet. He kept five rows: sleep duration, morning resting heart rate, two weekly bloods that mattered to him, and a single-sentence weekly note about how the week had felt. He fed the spreadsheet to a reasoning chat tool every Sunday with the same prompt: what would an honest observer notice this week. Then he read the answer. Then he closed the laptop.

The work was a five-row spreadsheet, a Sunday read-back, and the discipline of not adding columns. He kept the wearable, the sensor, the bloods. He stopped consulting them daily. The five rows were what he looked at. The reasoning chat was a colleague who had read his week. The decisions, when they came, were his.

His wife noticed he had stopped narrating his resting heart rate at breakfast.