The best prescription may well be the one that is never written. The first time I had to stock my doctor’s bag, I filled it neatly with every drug I could conceivably require to administer in an emergency, and several dozen more besides. Every few months, when I review the best before dates, I am aware of ordering smaller and smaller quantities to replace what is thrown out.

A few months ago, I told a medical student that there were probably fewer than 20 drugs that I would routinely use, and that I would have to look up the doses of anything else. She stared back at me with the kind of unbelieving horror one saves for true heretics.