Thomas Young (1773–1829) was a dazzling English polymath — physician, physicist, and puzzle-solver — who could read at two and spoke a small library of languages. With one beautifully simple experiment he proved that light behaves like a wave.
Young shone light through two narrow slits and, instead of two bright spots, got a striped pattern
of light and dark bands on the far wall. The only way to explain those stripes is
Physics was only one of Young's hobbies. He was among the first to make real progress decoding the hieroglyphs on the Rosetta Stone, helping unlock a language silent for over a thousand years. He also worked out how the eye focuses and why we see colour, and even estimated the size of molecules. His contemporaries nicknamed him "Phenomenon Young" — because he seemed to be an expert at absolutely everything.