Category: time-and-causality
Type: puzzle
Associated thinker(s): Aristotle
Original publication or approximate period: Aristotle, De Interpretatione, chapter 9 (fourth century BCE); its interpretation is disputed
Difficulty: Advanced
Themes: future contingents, fatalism, truth and time
Related experiments: Laplace’s Demon; The Consequence Argument; The Idle Argument
Suppose someone says today, “There will be a sea battle tomorrow.” Either the sentence is true or it is false. If it is true now, then it seems that the battle is already settled and cannot fail to occur. If it is false now, the battle cannot occur. Either way, whether there is a battle seems to be necessary and beyond anyone’s power to change, and deliberation about it is pointless.
Aristotle’s discussion of this case is brief and has been read in many ways.
Can statements about contingent future events be true or false now without making the future fixed?
The puzzle links logic, time and freedom. It asks whether every statement about a contingent future must already be true or false (bivalence), and how that question relates to excluded middle (that either p or not-p). On one influential reconstruction, bivalence together with assumptions about past truth and necessity threatens an open future. Aristotle’s closing distinction preserves that a sea battle either will or will not occur without making either outcome necessary. Rejecting bivalence is one response, but it is not the only way to resist the fatalist inference.
It also bears on the semantics of tense and on arguments about fatalism, determinism and planning.
These are later semantic frameworks for handling future contingents, not positions Aristotle explicitly names. Three-valued or truth-value-gap views treat future contingents as neither true nor false yet (or assign them a third, “undetermined” value); this is one disputed interpretation of Aristotle. Branching-time semantics evaluates claims against possible histories. In supervaluationism, a future contingent is neither true nor false at a moment when histories disagree, although its disjunction with its negation can still be true. In Prior’s Ockhamist model, a future statement can be true relative to a particular history without being settled at the branching moment; this differs from William of Ockham’s own view that future contingents may be true or false, though their truth is unknowable to humans but known by God. Prior’s Peircean model counts a future claim as true only if its outcome holds across all possible histories, so genuinely contingent “will p” and “will not p” claims are both false.
The puzzle is not a claim that the future is determined by logic. The fatalist’s move from a future statement’s truth (or falsity) now to the event’s necessity (or impossibility) is contested; the classical argument also relies on assumptions about past truth. Bivalence and excluded middle are distinct, and disputing the first need not mean rejecting the second. Aristotle’s own account remains disputed: scholars disagree about whether he denies bivalence for future contingents or instead restricts a related rule about contradictory pairs.
Modern versions ask about statements concerning free decisions, or involve foreknowledge by an infallible being. They bring in theological premises, which should be listed separately.
Aristotle’s On Interpretation, chapter 9, was consulted in the Revised Oxford Translation (Bekker 18a28–19b4), with the Edghill translation used as a cross-check. Relevant sections of the Stanford Encyclopedia of Philosophy entry on future contingents and M. A. Istvan Jr.’s analysis were read. The entry’s account of competing readings is summarized here; no claim is made about which reading is correct.
Research check: 2026-11-01. The earlier expansion record documents topic-keyword checking of the SEP page only, not passage-level reading; this audit directly checked the sources above. This is an original educational explanation, not a substitute for the primary texts. Additional comparisons are teaching prompts, not established historical variations.