Heisenberg Uncertainty Principle
This principle claims that one cannot know both the momentum and the position of any given thing at any given time. This, of course, is because anything with momentum has a constantly changing position. The principle derives its name from the sobering tragedy of the Heisenberg, a German zeppelin that caught fire in 1937. (The pilots of the Heisenberg knew their position* but not their momentum.) This principle affects everything from other forms of transportation to personal relationships. One might, for instance, use the H.U.P. to rebut the claim "This is headed nowhere," only to hear "Drew, our relationship is a flaming wreck."