Monday, June 6, 2016

An argument that Trans-World Depravity is unlikely to be true

Assume Molinism. Plantinga's Trans-World Depravity (TWD) is the thesis that every feasible world--world compatible with the conditionals of free will--that contains at least one significantly free choice contains at least one sin. I want to think about an argument that TWD is likely false.

For consider a world where God creates exactly one intelligent creature with the typical motivations and character of a typical morally upright adult human being. God then forbids the creature from imposing pointless pain on itself, and only ever gives the creature only one significantly free choice: to eat a nutritious food that it likes or to endure five hours of torture. Let's imagine the situation where God creates such a creature and it's about to make that one significantly free choice. Call this circumstances C. Given what we know about decent human beings and their motivations, the creature would very likely eat the nutritious food rather than be tortured. Very well. So very likely the conditionals of free will are such that the world where the creature eats the nutritious food is feasible. But if that world is feasible, then TWD is false.

That was too quick. I jumped between answers to two different probabilistic questions:

  1. What is the epistemic probability of the Molinist conditional that were C to obtain, the creature would choose wrongly?
  2. Were C to obtain, what would be the chance of the creature choosing wrongly?
It is clear that the answer to (2) is "Very low." But to argue that TWD is very likely false, I have to say that the answer to (1) is also "very low". This leads to a difficult set of questions about the relationship between Molinist conditionals and chances. Lewis's principal principle does imply that if we were to knowingly (with certainty) find ourselves in C, and if we were certain of Molinism, we would have to give the same answer to (1) and (2). The argument goes as follows: given C the Molinist conditional has the same epistemic probability as its consequent, but the epistemic probability of its consequent is the same as its chance by the principal principle. But the answer we should give to (2) in those circumstances where we were knowingly in C may not be the same as answer as we should actually give to (2). Consider this possibility. Our current epistemic probability of the Molinist conditional in (1) is 1/2, but God would be very unlikely to make C obtain unless the conditional were false. He just wouldn't want to create a world where the creature would freely wrongfully choose to endure the torture. In that case, if we were to learn that C obtains, that would give us information that the Molinist conditional is very likely false. And hence the answer to (1) is "1/2", the answer to (2) is "Very low", but were C to obtain, the answer to (1) would be "Very low" as well.

Maybe. But I think things may be even less clear. For the biased sampling involved in God's choosing what to create on the basis of conditionals of free will undercuts the principal principle, I think. I think more work is needed to be done to figure out whether or not there is a good argument against TWD here or not.


Heath White said...

Here is a somewhat different argument (I think simpler):

It is extraordinarily unlikely that God cannot come up with an agent/world pair where the *first* morally significant action of the agent is morally permissible. But then he could just zap the agent dead as soon as she did something decent. That would be a counterexample to TWD.

If God cannot create an agent who goes right the first time, that itself would be a pretty important theological fact.

Alexander R Pruss said...


It seems intuitively extraordinarily unlikely, but to cash out that intuition requires some more assumptions.

One way would be an independence assumption: The conditionals of free will in worlds that have no individuals in common are probabilistically independent. Then we generate an infinite sequence of worlds that have only one agent who has only one significantly free choice, a different individual in each world. Then as long as we can say that each conditional of free will has at least, say, a one in a billion chance of coming out in favor of the decent action, then the law of large numbers tells us that with probability one infinitely many of them are in favor of the decent action, and so with probability one TWD is false.

The independence assumption is highly intuitive, but I don't know how to justify it. The whole question of how to assign probabilities to conditionals of free will is difficult.

If the Adams thesis is true (probability of conditional = conditional probability), we get some help with probability assignments. But the Adams thesis is widely rejected.

Heath White said...

I think about it the other way around. Consider the infinite sequence of worlds consisting of one agent making a morally significant free choice. Now suppose, for quasi-reductio, that TWD is true and none of these initial choices are good. Therefore, the assumption of Transworld Depravity implies the much stronger assumption of Transworld Initial Depravity.

Wouldn't that be a remarkable fact? Wouldn't it need some kind of explanation of a sort no Molinist has attempted?

Plantingan Reply: no, because this is a defense, not a theodicy. I'm telling just-so stories, mere counterexamples to the necessities alleged by the logical problem of evil.

But the Plantingan reply is not available to the serious believing Molinist. It seems to me that you cannot (1) allege remarkable theological facts because they would be convenient for your theory and then (2) refuse to provide any explanation for them. This is to use the epistemic standards for a defense when putting forward a theodicy/world-picture proposed for belief.

Alexander R Pruss said...

How about the explanation: bad coincidence?
In practice, the Molinist can complicate the story. Presumably it's not God's aim to produce one good free choice. He probably wants lots of them by lots of agents.

Heath White said...

I agree about the "in practice" point. But then the Molinist is not disagreeing with Mackie's "an omnipotent agent can eliminate all evil" but instead is disagreeing with "a perfectly good agent would eliminate evil so far as it can."

BTW, I think my point about lack of explanation applies to TWD, not just TWID. And I don't think you can (responsibly) appeal to coincidences over infinite numbers of agents.

Alexander R Pruss said...

Well, every classical theist agrees with "an omnipotent agent can eliminate all evil". If God creates nothing, or nothing but one happy and unfree mathematician, then he has eliminated all evil. The question is about price.

The FWD says: "Possibly: God can't have a significantly free creature and no evil."

But one could instead say: "Possibly: God can't have a world rich in significant freedom and no evil."

Heath White said...

Yes, one could say that, and I think it would be more plausible than the original claim of the FWD. However, you are at that point objecting to the moral claims of the logical problem of evil, rather than the metaphysical claim. Once you do that, it seems to me that there are a lot more ways to reject those moral claims which don't depend on libertarian free will.