 Discussions of temporality and reasoning about time go back to antiquity, and examples can be found even in the Bible (Boyd 2014). Zeno’s famous flying arrow paradox refers to the nature of time and broaches the corresponding notion of change. Much of the early temporal discussion, however, centered around the problem of future contingents, that is, the question whether statements about future events that are neither necessary nor impossible can have definite truth values. The most widely known and probably most cited example is the sea-fight scenario discussed by Aristotle in On Interpretation (Chapter 9). Aristotle argued that statements such as “There will be a sea-fight tomorrow”, as well as the contrary prediction “There will not be a sea-fight tomorrow”, do not hold of necessity and hence lack definite truth values at present, while conceding that it is necessary that either there will be a sea-fight tomorrow or not. A few decades later, the philosopher Diodorus Chronus demonstrated the problem of future contingents in his famous Master Argument, which led him to define the possible as “what is or will be the case”. A detailed discussion of Diodorus’ argument is provided in e.g. Rescher and Urquhart (1971, Chapter XVII) and the entry on  future contingents.