On Tooley On Inductive Logic And The Evidential Argument From Evil
May 24, 2010 — 8:35

Author: Ted Poston  Category: Existence of God Problem of Evil  Comments: 6

Michael Tooley’s SEP article on the problem of evil is an excellent and thorough introduction to the problem of evil. In section 3.5 Tooley focuses on the inferential step from (a) there appear to be no goods that justify God in permitting some evils to (b) there are no goods that justify God in permitting some evils. My presentation involves a simplification to Tooley’s discussion and also a change from deontological terminology to axiological terms, but these changes are inessential for the point I want to make. Tooley has an interesting defense of this inference in light of the unknown goods move. He imagines that there might be some unknown good that would justify God in permitting evil. But he then claims that the probability that there’d be some such good is equal to the probability that there’d be some unknown evil. So on the assumption that we are prima facie justified in believing (b) on the basis of (a), Tooley reasons that appeals to unknown goods don’t help. Why? There are four possibilities: (i) the unknown good obtains and no unknown evil obtains; (ii) the unknown good obtains and an unknown evil obtains; (iii) no unknown good obtains and no unknown evil obtains; and (iv) no unknown good obtains and some unknown evil obtains. Tooley then observes that in three of these four cases, the original problematic state of affairs remains impermissible. It’s only in (i) that the original problematic state of affairs is justified. Tooley mentions that all this needs tightening up, but the main intuition is relatively clear. I think there are several lines of response to Tooley’s argument, but I want to consider a smallish point that I think Tooley may agree with. The point is that the unknown goods defense accomplishes this: it lessens the evidential burden on theism by raising the probability of theism. I’ll put the details below the fold.


To see this consider this simple analogy: Suppose there are four states of affairs that may attain {1, 2, 3, 4}. You can imagine that these are four sides of a die. If one adopts an indifference principle, then in the situation of ignorance, one should assign a probability of .25 to each outcome. So in this setup one is justified in believing that a non-1 will occur. Now let’s add some complication: there are four processes by which one (or more) of these states of affairs may occur: A, B, C, D. Suppose that process A always yields a 1, and the other three processes are entirely random. So, now what’s the probability that you’d get a non-1? It’s 1 – the probability that a 1 would occur by one of these four processes. And that is 1-.4375, assuming I’ve calculated correctly. So in this complication the probability that a non-1 occurs is .5625. Is one still justified in believing that a non-1 resulted? Yes. But notice that there’s been a significant epistemic change: one’s probability that a non-1 results has decreased from .75 to .5625. I think a similar judgment holds accepting everything that Tooley says: one still isn’t justified in believing that there’s a God given evil but the justificatory burden is lessened by the move to unknown goods (see footnote 2). The significance of this lies in the total evidence condition. If one now adds in more evidence for theism, the unknown goods move makes it easier to justify theism. Another way to see this point is that Tooley focuses on the final probability of theism given evil. He’s right that given the unknown goods move the final probability of theism doesn’t go to .5 or above. But if one focuses on the probability dynamics the unknown goods move does significantly raise the probability of theism. I think this is an important result if one adopts Swinburne’s approach to justifying theism in which one starts with some evidence, gets a probability on theism, adds some more evidence, gets another probability and so on, until one has added in all the evidence. What the unknown goods move does is move the probability of theism up given evil. Thus, if there’s more evidence to add in its quite possible that the probability of theism goes to .5 or above.
Footnote 1: Tooley’s presentation in 3.5 tries to generalize the result so that as one adds more and more apparently unjustified evils the probability of theism goes down (see the last paragraph of 3.5). But the unknown goods move shows that this kind of response doesn’t work. Just reapply Tooley’s strategy for an unknown good that would justify all these evils. In other words, the unknown goods strategy generalizes in a way that Tooley seemingly doesn’t allow for.
Footnote 2: Suppose the probability of (b) given (a) is very high, say, .99. Now consider these probabilities using the letters as defined above. Pr(b/a&(i))=0; Pr(b/a&(ii))=Pr(b/a&(iii))=Pr(b/a&(iv))=1. The result: the Pr(b/a)=Pr(b/a&(i))+Pr(b/a&~(i)=0+.75=.75. This assumes an indifference principle. Upshot: Tooley’s move results in Pr(b/a) being lowered from .99 to .75. If one focuses on final probability alone you lose the result that there’s been significant epistemic change.

Comments:
  • Mike Almeida

    Ted, you write,
    Tooley reasons that appeals to unknown goods don’t help. Why? There are four possibilities: (i) the unknown good obtains and no unknown evil obtains; (ii) the unknown good obtains and an unknown evil obtains; (iii) no unknown good obtains and no unknown evil obtains; and (iv) no unknown good obtains and some unknown evil obtains. Tooley then observes that in three of these four cases, the original problematic state of affairs remains impermissible
    I can’t see how only (i) makes the evil that obtains justified. Suppose (ii) is true and the unknown good justifies both the unknown evil and the known evil. Suppose (iii) is true and the unknown good does not obtain but will. Those too are unknown goods. Does he stipulate these out?

    May 24, 2010 — 16:05
  • Ted Poston

    Hi Mike,
    Tooley stipulates that the unknown good and unknown evil are equal in weight. (He puts it in deontological terms, i.e., right-making property and wrong-making property). Thus, in (ii) the unknown stuff doesn’t change the evidential situation. With (iii) you can read it as “no unknown good obtains or will obtain and no unknown evil obtains or will obtain. The idea is that there’s a simple matrix and you distribute probability evenly across the matrix. Let G be the claim that an unknown good obtains or will obtain and E be the claim that an unknown evil obtains or will obtain. Stipulate that the weight of G is equal to E. I think Tooley says that apriori we don’t have any reason to think that G would outweigh E. So then we have the four states of affairs: (i) G and not E; (ii) G and E; (iii) not G and not E; and (iv) not G and E.

    May 24, 2010 — 16:59
  • Mike Almeida

    I think Tooley says that apriori we don’t have any reason to think that G would outweigh E.
    I agree. But we wouldn’t have any apriori reason that it wouldn’t. It looks to me like Tooley hasn’t sufficently fine-gained the possible outcomes. You can make four outcomes (two for that matter) exclusive and exhaustive, but only if you cut things very coarsely and neglect some genuine possibilities. No?

    May 24, 2010 — 17:19
  • Ted Poston

    Good point. So let’s see: if we represent variance in weight we have 12 possibilities: in the case in which G outweighs E, 2 of the 4 cases are favorable to theism; in the case in which G and E have equal weight it’s 1 of 4 and in the other case it’s still 1 out of 4. So the favorable cases to theism are 4 out of 12 or 1/3. Is this what you had in mind?

    May 24, 2010 — 17:47
  • Ted Poston

    Here’s another way to understand the point. Suppose you think the probability of gratuitous evil given apparently gratuitous evil is .99. But then you observe that there are four relevant states of the world that depend on whether there’s some great unforeseen good. In 3 of those 4 states apparently gratuitous evils are gratuitous but in 1 those *apparently* gratuitous evils aren’t gratuitous. So, now, how should you update? You should think there’s a 25% chance that the evil isn’t really gratuitous. So look what Tooley’s move has done: it’s raised the probability of theism from .01 to .25! (Given Mike’s point above: the probability of theism goes from .01 to .33).

    May 25, 2010 — 8:20
  • Mike Almeida

    Hi Ted,
    Right, the worry is in knowing apriori the number of possible outcomes. One expects–I do anyway–that the number is larger and finer-grained than Tooley suggests. But there is another worry. The skeptical theist will allow that there might be some unknown goods, since God’s purposes might beyond our ken. But few skeptical theists (Bergmann might be an exception) would urge that there are equally good reasons to believe that there might be unknown evils. That is, the rationale for the possibility of unknown goods is that God’s purposes for allowing evil might be less than transparent to us. There is no symmetrical rationale for the possibility of unknown evils. The only way to get the symmetry is to argue from value skepticism that would obtain whether or not God existed. The value skepticism that is induced only if God exists is an asymmetrical skepticism about unknown goods (unknown because God-purposed goods are not likely to be known!). But there are no evils that are unknown because God-purposed evils are not likely to be known.

    May 25, 2010 — 11:40