Do you remember the prediction, made in 1999, that the DOW would reach 36,000 in a few years? Since that didn't happen, I am inclined to say that Glassman and Hasset's prediction was wrong and was wrong at the time the prediction was made. I take that to mean that the content of their prediction was false at the time the prediction was made. Subsequent events merely made it evident that the content of the prediction was false; said events did not first bring it about that the content of the prediction have a truth-value.
And so I am not inclined to say that the content of their irrationally exuberant prediction was neither true nor false at the time of the prediction. It had a truth-value at the time of the prediction; it was simply not evident at that time what that truth-value was. By 'the content of the prediction' I mean the proposition expressed by 'The DOW will reach 36,000 in a few years.'
I am also inclined to say that the contents of some predictions are true at the time the predictions are made, and thus true in advance of the events predicted. I am not inclined to say that these predictions were neither true nor false at the time they were made. Suppose I predict some event E and E comes to pass. You might say to me, "You were right to predict the occurrence of E." You would not say to me, "Although the content of your prediction was neither true nor false at the time of your prediction, said content has now acquired the truth-value, true."
It is worth noting that the expression 'come true' is ambiguous. It could mean 'come to be known to be true' or it could mean 'come to have the truth-value, true.' I am inclined to read it the first way. Accordingly, when a prediction 'comes true,' what that means is that the prediction which all along was true, and thus true in advance of the contingent event predicted, is now known to be true.
So far, then, I am inclined to say that the Law of Excluded Middle applies to future-tensed sentences. If we assume Bivalence (that there are exactly two truth-values), then the Law of Excluded Middle (LEM)can be formulated as follows. For any proposition p, either p is true or p is false. Now consider a future-tensed sentence that refers to some event that is neither impossible nor necessary. An example is the DOW sentence above or 'Tom will get tenure in 2014.' Someone who assertively utters a sentence such as this makes a prediction. What I am currently puzzling over is whether any predictions, at the time that they are made, have a truth-value, i.e., (assuming Bivalence), are either true or false.
Why should I be puzzling over this? Well, despite the strong linguistic inclinations recorded above, there is something strange in regarding a contingent proposition about a future event as either true or false in advance of the event's occurrence or nonoccurrence. How could a contingent proposition be true before the event occurs that alone could make it true?
Our problem can be set forth as an antilogism or aporetic triad:
1. U-LEM: LEM applies unrestrictedly to all declarative sentences, whatever their tense.
2. Presentism: Only what exists at present exists.
3. Truth-Maker Principle: Every contingent truth has a truth-maker.
Each limb of the triad is plausible. But they can't all be true. The conjunction of any two entails the negation of the third. Corresponding to our (inconsistent) antilogism there are three (valid) syllogisms each of which is an argument to the negation of one of the limbs from the other two limbs.
If there is no compelling reason to adopt one ofthese syllogisms over the other two, then I would say that the problem is a genuine aporia, an insoluble problem.
People don't like to admit that there are insolubilia. That may merely reflect their dogmatism and overpowering need for doxastic security. Man is a proud critter loathe to confess the infirmity of reason.
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