 In the ancient world, a number of arguments were put forward that proceed from the Principle of Bivalence, a basic principle in logic, in order to establish fatalism—where “fatalism” is the view that the future is inevitable and we are powerless to do anything to shape it. Most prominently, these arguments are presented in chapter 9 of On Interpretation, Aristotle’s treatise on semantics, and in Cicero’s On Fate, which discusses the “Lazy Argument”. The “Master Argument”, a similar argument for the necessity of the future that was taken to have fatalist implications, is both put forward and endorsed by Diodorus Cronus (died c. 284 BCE). These arguments differ in their details, but in broad strokes here is how they all proceed. (Henceforward, “the fatalist argument” refers to this general argument.)