Archimedes

Archimedes of Syracuse was the greatest mathematician of the ancient world, and perhaps its most inventive mind. Legend says he leapt from his bath shouting 'Eureka!' — I have found it! — having realized, watching the water rise, how to measure the volume of an irregular crown and so detect a goldsmith's fraud. The story may be embroidered, but the genius behind it was not.

He calculated pi more precisely than anyone before him, found the area under a parabola by methods that anticipated calculus by nearly two thousand years, and worked out the mathematics of levers, pulleys, and floating bodies. 'Give me a place to stand,' he is supposed to have said of the lever, 'and I will move the Earth.' When Rome besieged his city, he turned his mind to war machines so fearsome that the soldiers came to dread the sight of a rope or beam rising over the walls.

When Syracuse finally fell, a Roman soldier found the old man absorbed in a geometric diagram drawn in the sand. 'Do not disturb my circles,' he said — and was killed for it. We honor him as the mind that married pure thought to the physical world — proof that the deepest mathematics is also the most practical, and that a single thinker, given a place to stand, really can move the world.