What to teach the brightest and best

摘要

I can still remember the day my first-year tutor sat implacably in his swivel-chair in front of us and proceeded to apply the blade of a dirty knife to the flesh of a toothsome-looking apple. Having operated on the apple, he displayed its severed half to his perplexed audience, cut face uppermost. "This," he intoned, with suitable pause for effect, "is a plan." Tilting the fruit through 90 degrees he was able to make further use of it as a live demonstration of the principle of section and elevation.