par·a·dox

noun: a seemingly absurd idea, statement or approach that when investigated may prove to be true or useful.

history: The ancient Greeks were well aware that a paradox—the saying “less is more,” for example—can take us outside our usual way of thinking. They combined the prefix para-, “beyond” or “outside of,” with the verb dokein, “to think,” forming paradoxos, an adjective meaning “contrary to expectation.” Latin speakers used that word as the basis for a noun paradoxum, which English speakers borrowed during the 1500s as “paradox”.