In 2010 I wrote about Ideas Behind Their Time : We are all familiar with ideas said to be ahead of their time, Babbage’s  analytical engine  and da Vinci’s  helicopter  are classic examples.  We are also familiar with ideas “of their time,” ideas that were “in the air” and thus were often simultaneously discovered such as the telephone, calculus, evolution, and color photography.  What is less commented on is the third possibility, ideas that could have been discovered much earlier but which were not,  ideas behind their time . I gave experimental economics, random clinical trials and view morphing (“bullet time”) as examples. Jason Crawford has a list discussing the wheel, the steam engine and bicycles among other possibilities. In some cases, further exploration indicates that an idea required precursors and so was not as behind its times as first suspected, in rare cases, however, good ideas really could have been invented much earlier.…