Goofs

(at around 12 mins) When discussing Columbus' journey John implies that there was still widespread belief that the earth was flat. In fact, since the time of the Greeks it had been relatively common (educated) knowledge that the earth was round. (Columbus' error was in underestimating the diameter of the earth and thus the distance to Asia by a westerly route. Luckily, he bumped into the Americas where he'd roughly calculated Asia was supposed to be, otherwise they'd have been lost at sea.) See more