Suppose I know that if I go kayaking on a sunny day for two delightful hours, I will have mild muscle pains the next day. I judge that the price is well worth paying. I go kayaking and I then suffer the mild muscle pains the next day.
My suffering is not deserved. After all, suffering is something you come to deserve by wrongdoing, and I haven't done anything wrong. But it's also awkward to call it "undeserved". I guess it's non-deserved suffering.
It would be very implausible to run an argument from evil based on a case like this. And it's not hard to come up with a theodicy for it. God is under no obligation to make it possible for me to go kayaking on a sunny day and a fortiori he is under no obligation to make it possible for me to do so while avoiding subsequent pain. It is not difficult to think that the good of uniformity of nature justifies God's non-interference.
How far can a theodicy of this sort be made to go? Well, it extends to other cases where the suffering is a predictable lawlike consequence of one's optional activities. This will include cases where the optional activities are good, neutral or bad. Maimonedes, no doubt speaking from medical experience, talks of the last case at length:
The third class of evils comprises those which every one causes to himself by his own action. This is the largest class, and is far more numerous than the second class. It is especially of these evils that all men complain,only few men are found that do not sin against themselves by this kind of evil. Those that are afflicted with it are therefore justly blamed .... This class of evils originates in man's vices, such as excessive desire for eating, drinking, and love; indulgence in these things in undue measure, or in improper manner, or partaking of bad food. (Guide for the Perplexed, XII)
Maimonedes divides evils into three classes:
- evils caused by embodiment,
- evils inflicted by us on one another, and
- self-inflicted evils.
The last remark is quite interesting. It goes against the grain of us analytic philosophers—exceptions are our bread and butter, it seems. But Maimonedes' insight, which mirrors Aristotle's remarks about precision in ethics, is deep and important. It suggests that the evils for which there is a plausible "problem of evil", namely the evils of the first and second classes, are an anomaly, and should be handled as such (for a development of this idea, see this paper by Dougherty and Pruss, in Oxford Studies).