By the time solar power was rediscovered by Leonardo da Vinci his urge to 'think new thoughts and bring new things into being' meant that while other people were eating their own snot he was anatomising elephants and inventing the hang glider. He even managed to squeeze the classic Vituvian Man out of an incident when a naked moron climbed onto his skylight. Born illegitimate, da Vinci had been spared the rusty harness of formal schooling and fell back on mere curiosity and honest observation of an infinite universe.