Sir

Towards the end of your interview with Daedalus, he points out that even Sir Peter Medawar felt that 80% of his research activity had been completely wasted, and that this is a typical record (Nature 390, 126–127; 1997). Perhaps his main point was that a 20%-efficient activity shouldn't be taken too seriously. But can Daedalus suggest an entropy-defying device by which I can determine which of my activities belong in the 80% ‘fruitless’ category — and trade those for exploring not-so-serious, unconventional ‘mad’ experiments?