writes "In 1818, the French Academy of Sciences held a contest to explain the nature of light. One of the entrants was Fresnel, who put forth an elaborately advanced model that light was a wave. One of the judges was Simeon Poisson, passionate defender of Newton's corpuscular model, who showed that Fresnel's results absurdly predicted that light shone around a circular obstacle would result in a bright spot at the center, and basically had Fresnel laughed out of the room. But he committed the cardinal sin of drawing that conclusion without anyone actually performing the crucial experiment! Thankfully, François Arago was there to set things right."