## Monday, January 21, 2013

### Open future and logic

Typical human languages (maybe all natural human language) have a "Was" operator that applies to a sentence s and yields a sentence Wast(s) that backdates s to t. Sometimes that operator works by shifting context, but in English it normally works by shifting tense and inserting an "at" (though sometimes a more complex formulation is needed). Thus, perhaps, "Wast(George is talking about Saddam Hussein)" is the sentence: "George was talking about Saddam Hussein at t".

Now, here are two plausible facts about logic and the Wast(s) operator:

1. If the proposition that s entails the proposition that u, then the proposition that Wast(s) entails the proposition that Wast(u).
2. For every proposition p, p entails the proposition that p is true.
Moreover:
1. That Hitler's actions are starting a world war entails that there is or will be a world war.
Let t be September 1, 1939. Then:
1. Hitler's actions were starting a world war at t. (Historical fact)
2. Wast(Hitler's actions are starting a world war). (Paraphrase of 4)
3. Wast(There is or will be a world war). (By 1, 3 and 5)
4. Wast(The proposition that there is or will be a world war is true). (By 1, 2 and 6)
5. The proposition that there is or will be a world war was true on September 1, 1939. (Paraphrase of 7)
But if (8) is true, then open future views are false. For on September 1, 1939, whether there would be a world war depended at least in part on the free choices of Poland's whether or not to honor their promises to Poland, free choices that British and French leaders made over the next two days.

Alan Rhoda has already denied (2), calling it "Pruss's mistake". So he won't have any trouble with this argument. But (2) seems rather more plausible than the conjunctions of the premises of the best arguments for open future views.

I should say that I am not sure (2) is true. What I am more sure of is:

1. For every proposition p, p entails the material conditional: if p exists, p is true.
But the argument can be adapted to use (9) in place of (2), since it's very plausible that the proposition that there is or will be a world war existed at t. The reason why (9) may need to replace (2) is issues with de re propositions. For instance, in a world where Socrates never comes into existence the proposition that Socrates never comes into existence might not exist, and hence might not be true.

Michael Gonzalez said...

Forgive me if I'm not seeing this correctly, but it seems to me that your biggest mistake is in #3. I think #2 is actually rather plausible. But #3, where you say that "Hitler is starting a war" entails that there "is or will be a war" seems broken in the following way:

If "Hitler is starting a war" entails that there is or will be a war, then if we position ourselves at t, the statement "Hitler is starting a war" is actually not true. The statement "Hitler is attempting to start a war" is certainly true, but since his success depends on free choices of others, the statement "Hitler is starting a war" is false. The starting of the war isn't entirely up to Hitler, so to say that he was definitely starting a war would be false even if he had succeeded (in which case, the full proposition is something like "Hitler attempted to start a war, and the free actions of those in power permitted this attempt to come to fruition"....

Alexander R Pruss said...

I think you're denying 4, not 3.

But we do indeed say things like: "In 1982, Michelle married the future president of the United States." And that one is marrying the future president of the United States entails that the person one is marrying will be president of the United States. I could have used that in my argument.

Michael Gonzalez said...

But, in 1982, Barack wasn't the future president of the United States. It is only in retrospect that that label applies. This gets back to a fundamental point about time (at least, for A-theorists): a truth about the past, seen from the present, was not necessarily a truth at that moment in the past.

Michael Gonzalez said...

And, it seems to me that Libertarian free will absolutely requires this understanding. If there were a "fact of the matter" about Barack becoming the president back when Michelle married him, then it would follow that none of us had any choice in electing him. Since there was no such fact of the matter, we can be seen as free agents, choosing from an open future.

Alexander R Pruss said...

So, from hindsight we say that in 1982 Michelle Obama married the future president of the United States. Is this thing we say true or false?

Nathan Coppedge said...

"That Hitler's actions are starting a world war entails that there is or will be a world war."

Maybe this is an understated claim, but I think that this phrase (#4) is what you should deny.

The only reason we think that Hitler caused a world war is significant is because it happened. It is still possible that something else might have happened that was more significant.

Because the other more significant thing might or might not have interrupted the world war, it is clear that something else could have caused, or instead failed to interrupt, the world war. What physical boundary is to keep us from thinking that these absences of cataclysms or absences of saving-grace, or throws of the dice, are not just as significant as the specific motivations or properties of Hitler which made him responsible for the World War?

I'm not intending to defend Hitler, but it seems worth saying that by assuming in one premise that Hitler caused the world war, we are not rejecting the contingency thesis that something else could have been equally important, even enough so to avert the war.

We can't assume that Hitler's causing the war was as important as everything else. For example, what if there were a God? Or what if there were a Goddess of History? Or what if Hitler's actions were not self-determined? These sorts of things blow open the bubble. I generally think determinism without free will is a floppy fish, since free-will is a form of determinism, albeit not universal determinism. Thus all efforts at arguing for determinism should argue for universal determinism. But consistently this is not what they do. And there are forms of evidence that it is not easily done.

Michael Gonzalez said...

"So, from hindsight we say that in 1982 Michelle Obama married the future president of the United States. Is this thing we say true or false?"

It is presently true that the man Michelle married in 1982 became the president. It was not true in1982 that he would become president. So the statement you make is false, and is phrased in such a way as presumes that the future was predetermined.