Is “It Will Rain Tomorrow” Already True or False?

If it rains tomorrow, we may say that today’s statement, “It will rain tomorrow”, was correct. But before the rain falls, is the statement already true? If it is, does that make tomorrow’s rain unavoidable? This is the problem of future contingents. It is not merely about forecasting accuracy, but about the relation among truth, time and necessity.

In chapter 9 of On Interpretation, Aristotle uses the example of a sea battle tomorrow. If every affirmation and denial about the future is already determinately true or false, it can seem that whatever the true statement describes must occur regardless of anyone’s choices, allowing logic to erase contingency. Yet Aristotle also maintains that what is necessary is the whole alternative — a battle will occur or it will not — not that either member is now necessary. Scholars still disagree about his precise solution. One reading denies a determinate present truth-value to future contingents; another preserves bivalence while rejecting the move from truth to necessity.

Return to rain. A forecast gives a forty per cent chance, and we can still plan a picnic while arranging an indoor alternative. If rain arrives, the earlier sentence can be judged true in retrospect. But its later truth does not mean that the sentence caused the rain, or that every contrary development was already logically impossible. Truth concerns whether a statement matches the facts; necessity concerns whether the facts could not have been otherwise. The two are not interchangeable.

My view is that we need not first settle whether every future sentence already has a truth-value in order to preserve meaningful choice. Three levels should be kept apart: what we know, the semantic rule used to assess the sentence, and whether the causal world still permits different outcomes. Ignorance does not prove the absence of truth, while truth does not amount to fate. Practical decisions should follow evidence, probability and changeable conditions, not mistake “later shown to be true” for “already destined now”.

Sources: https://classics.mit.edu/Aristotle/interpretation.1.1.html
https://plato.stanford.edu/entries/aristotle-logic/