Today's puzzle will be posed in two halves. The first half is a classic riddle – in fact, I suspect many of you will have heard it before. The second half, however, is an extension of the riddle that reveals its most common solution be be insufficient.
Almost two millennia before the rest of humanity entered the industrial age, the Greek inventor Hero invented the steam engine, wind-powered machinery, and theories of light that couldn't be improved for centuries. And then he invented some really crazy stuff.
One of the world's most ancient math puzzles, the magic square has traditionally been a numbers game. Electrical engineer Lee Sallows gives the ancient construct shape, creating an entirely new sort of puzzle in the process.