Where does money come from? What is "the gold standard?" And, while we're at it -- what exactly is money?More to the point, what does the Constitution have to say about all of this? Quite a bit, it turns out. And at times in our constitutional history, Congress's power to "coin money, regulate the value thereof, and of foreign coin" has been front and center on the political and economic agenda.We'll speak with UC-Davis historian Eric Rauchway about his new book, "The Money Makers," which takes us back all the way to the Great Depression and a couple of fellows named Franklin Delano Roosevelt and John Maynard Keynes.