In previous posts, I’ve discussed skeptical theism and certain types of arguments from evil (i.e. Humean arguments from evil). My contention has been that it is plausible that skeptical theism doesn’t apply to certain Humean arguments from evil, particularly Draper-style arguments from evil. Recently, however, Timothy Perrine released a paper where he contests this by combining skeptical theism with a certain principle regarding belief.  More specifically, Perrine also responds to Draper’s ‘off-setting’ objection to skeptical theism.
A sketch of Draper’s argument:
Let O (for “observations”) represent the evidence to be explained, in this case observations about pain and pleasure. More formally, Draper defines O as a statement about “the kinds, amounts, and distribution of pain and pleasure in the world.” In Draper’s formulation, O is the conjunction (or combination) of the following:
O1 = a statement about facts concerning “moral agents experiencing pain or pleasure that we know to be biologically useful”;
O2 = a statement about facts concerning “sentient beings that are not moral agents experiencing pain or pleasure that we know to be biologically useful”; and
O3 = a statement about facts concerning “sentient beings experiencing pain or pleasure that we do not know to be biologically useful.”
So defined, Draper’s argument from the biological role of pain and pleasure runs as follows:
1. O is known to be true.
2. Theism (T) is not much more probable intrinsically than the hypothesis of indifference (HI) [i.e., Pr(|T|) is not much greater than Pr(|HI|)].
3. O is much more likely on the assumption that the hypothesis of indifference is true than it is on the assumption that theism is true [i.e., Pr(O | HI) >! Pr(O | T)].
4. So, other evidence held equal, theism is probably false. 
Skeptical Theism and Draper’s Response
With respect to skeptical theism, Draper responds by granting that, for all we know, God has a good reason for allowing various instances of suffering. But, says Draper, it is also true (and antecedently just as likely) that, for all we know, God doesn’t have a good reason for allowing various instances of suffering. Hence, we’re right back where we started, which is working with what we do know. Perrine labels this objection to skeptical theism ‘the off-setting objection’.
Response to Draper by Perrine
Timothy Perrine responds by first combining theism with skeptical theism. That is, skeptical theism is (arguably) very likely on theism. And, if this is the case, we can’t know that the third premise is true in Draper’s argument.
Next, in order to deal with Draper’s objection to skeptical theism, Tim combines skeptical theism and theism with a certain principle regarding belief. Tim calls the principle “Principle“. Tim summarizes it as follows: If a person reasonably believes that P is true only if Q is true (e.g. that P implies Q), and it is unreasonable for that person to believe that Q is true, then it is unreasonable for that person to believe P.
Also, Perrine gives the following illustration:
Suppose your students have done particularly poorly on the last in-class quiz. You claim that this data—poor quiz grades—is more probable given one hypothesis—they are incompetent—than another hypothesis—they are competent. In response, I point out that a competent but otherwise lazy and uninterested student will do just as poorly on a quiz as an incompetent one. Suppose, further, that you cannot reasonably rule out the possibility that most of your competent students are lazy and uninterested (it is early in the semester, say). Intuitively, it no longer remains reasonable for you to believe that the poor quiz grades are much more likely given that your students are incompetent than competent. Now imagine someone lodges an analogous offsetting objection:
But suppose you consider this possibility which you cannot reasonably rule out: for all you know, almost none of your competent students are lazy. This possibility “offsets” the other one. Therefore, it is now reasonable for you to once again believe that your initial data of poor quiz grades is much more likely given the hypothesis that they are incompetent than the hypothesis that they are competent.
This objection is intuitively unpersuasive.
Hence, Perrine isn’t just comparing the Pr(O|HI) to the Pr(O|T). Rather, he is comparing the Pr(O|HI) to the Pr(O|T & ST & P), where ST stands for ‘skeptical theism’ and P stands for ‘Principle’.
I’m not sure why we still shouldn’t accept that HI is a better explanation of the data of evil than Perrine’s expansive theism. Perrine adds an auxiliary hypothesis in the form of skeptical theism, and Perrine also adds his principle regarding belief. So, Perrine’s explanation is much less simple than the hypothesis of indifference.
Secondly, one can argue that human ignorance of God’s reasons for allowing evil is much more expected on the hypothesis of indifference than expansive theism. Expansive theism does give us some grounds for our ignorance, but our ignorance isn’t at all surprising given the hypothesis of indifference. That’s because HI entails that there is no Omnipotent and Omnibenevolent Being who cares about our ignorance. On the other hand, theism does not entail skeptical theism.
Thirdly, one can change Draper’s third premise, such that, the third premise is rendered only probably true, instead of being very probably true. This is relevant because Perrine’s principle applies to having an outright belief in a proposition. An outright belief in a proposition requires a confidence level of at least 60%. Thus, if Draper’s third premise in the argument is only trying to show that a person should have a confidence level >50%, then I don’t see how Perrine’s principle can apply. Similarly, Draper could argue that, given the data regarding evil, one should lower/raise their confidence level in God’s existence/non-existence.
Fourthly, one might wonder whether Perrine’s critique of Draper’s ‘offsetting’ objection is correct. Perrine cites instances where it doesn’t seem reasonable to continue to believe a claim when you can’t rule out a certain possibility, and this is still the case even if one can say (per Draper), “Well, it’s also possible that ~P.…”. The issue isn’t whether we can find counter-examples to Draper’s fundamental objection. Rather, we are only concerned with whether skeptical theism is like the examples that Perrine cites.
Finally, it should be noted that it’s not skeptical theism alone that is being used (by Perrine) to try and undermine Draper-style arguments from evil. Rather, he is utilizing skeptical theism + his principle.
 Perrine, T. SOPHIA (2018). https://doi.org/10.1007/s11841-018-0656-7
 For definitions of ‘theism’ and ‘hypothesis of indifference’, see my earlier posts or Draper’s articles.