I practice positive thinking every day

Anybody who has done physiotherapy after a knee operation knows the exercises matter most on the days they hurt. The comfortable repetitions are almost decoration.

The same shape holds here. On a good morning the optimism is free and barely counts as effort. It's the grey Tuesday version — done badly, done grudgingly, done for ninety seconds while the kettle boils — that is actually building something. It never feels impressive while it's happening, and the days you nearly skipped are the ones doing the work.