America’s distinctive contribution to philosophy is called pragmatism. Like all notions that have been marinated and masticated by generations of academic philosophers, this movement has been minced to bits. At the beginning, though, in the late 19th and early 20th centuries, pragmatism was a reaction by the likes of C.S. Peirce , William James and John Dewey to the idealistic philosophies of Europe. Truth is not to be found in some palace of the mind apart from the world, they argued. Rather, the truth of an idea is measurable by its effects.

Well, duh, you might say. And that’s sort of the point: All great and true philosophies eventually seem self-evident after enough experience. Pragmatism advanced largely because its alternative — analytical idealism — has been such a grotesque practical failure. Over the past century, grand theories of racial supremacy, nationalist destiny and communist utopia were repudiated by their terrible real-life effects. Even the more recent notion that the whole world hungers for American-style democracy has run aground on the reef of reality.

Most Americans aren’t philosophers, thank goodness, but we are a nation of pragmatists. And so, despite the snap to her zinger, Sen. Elizabeth Warren (Mass.) was out of the mainstream when she shrugged off criticism during the second round of Democratic debates by saying: “I don’t understand why anybody goes to all the trouble of running for president of the United States just to talk about what we really can’t do and shouldn’t fight for.” […]