While no one believes the ridiculous position that only atheists go to heaven, not even Richard Carrier himself, many people do believe things which allow for the construction of wagers in favor of things besides Christianity.
Other real religions would be a typical example. Thus Muslims probably generally believe that you are more likely to go heaven if you become a Muslim, and some of them believe that all non-Muslims go to hell. So they can argue that you should choose to believe that Islam is true, in order to increase your chances of going to heaven, and to avoid going to hell.
Similarly, some Catholics who hold a Feeneyite position hold not only that you must be a Catholic, externally and literally, in order to be saved, but that you also cannot be saved unless you accept this position. Since there is some chance that they are right, they might argue, you should choose to accept their position, in order to be more sure of getting to heaven and avoiding hell.
Likewise, a Catholic could argue that the Church teaches that the religious life is better than married life. This probably means that people choosing to embrace religious life are more likely to go to heaven, since it is unlikely that the chances are completely equal, and if getting married made you more likely to go to heaven, it would be better in an extremely important way. So if you are a single Catholic, you should choose to believe that you have a religious vocation, in order to maximize your chances of going to heaven.
It is instructive to consider these various wagers because they can give some sort of indication of what kinds of response are reasonable and what kinds are not, even to Pascal’s original wager.
A Christian would be likely to respond to the Islamic wager in this way: it is more likely that Christianity is true than Islam, and if Christianity is true, the Christian would increase his chances of going to hell, and decrease his chances of going to heaven, by converting to Islam, and especially for such a reason. This is much like Richard Carrier’s response to Pascal, but it is reasonable for Christians in a way in which it is not for Carrier, because Christianity is an actually existing religion, while his only-atheists-go-to-heaven religion is not.
A Catholic could respond to the Feeneyite wager in a similar way. The Feeneyite position is probably false, and probably contrary to the teaching of the Church, and therefore adopting it would be uncharitable to other people (by assuming that they are going to hell), and unfaithful to the Catholic Church (since the most reasonable interpretation of the Church’s teaching does not allow for this position.) So rather than increasing a person’s chances of going to heaven, adopting this position would decrease a person’s chances of this result. Again, the possibility of this answer derives from the fact that there are two already existing positions, so this answer does not benefit someone like Carrier.
It is more difficult for a Catholic to reject the religious vocation wager in a reasonable way, because the Church does teach that the religious life is better, and in fact this most likely does imply that Catholics embracing this form of life are more likely to be saved.
A Catholic could respond, “But I don’t actually have a religious vocation, and so I shouldn’t choose to believe that I do.” This is no different from a unbeliever saying, “But Christianity is not actually true, and so I shouldn’t choose to believe that it is.” And this response fails in both cases, because the arguments do not purport to establish that you have a vocation or that Christianity is true. They only intend to establish that it is better to believe these things, and such a response does not address the argument.
The Catholic could insist, “But if I don’t actually have a religious vocation, God does not want me to do that. So if I choose to believe in a vocation and follow it, I will be doing something that God does not want me to do. So I will be less likely to be saved.” This seems similar to the unbeliever responding, “If God exists, he does not want people believing things that are false, and Christianity is false. So I will be less likely to get anything good from God by believing.”
Both responses are problematic, basically because they are inconsistent with the principles that are assumed to be true in order to consider the situation. In other words, the response here by the Catholic is probably inconsistent with the teaching of the Church on religious vocations, and likewise the response by the unbeliever is obviously inconsistent with Christianity (since it denies it.) The reason the Catholic response is likely inconsistent with the teaching of the Church on vocations is that given that someone asserts that he has a religious vocation, the Church forbids other people from dissuading him from it on the supposed grounds that he does not have a real vocation. But if it were true that someone who chooses to believe that he has a vocation, and then acts on it, is less likely to be saved given that he did not really have a vocation, then it would be extremely reasonable for people to dissuade him. Since the Church forbids such dissuasion, it seems to imply that this answer is not correct.
Both responses can be modified so that they will be consistent with the situation under consideration. The Catholic can respond, “I very much do not want to live the religious life. Granted that the religious life in general would make someone more likely to be saved, I would be personally extremely miserable in it. This would tempt me to various vicious things, either as consequences of it, as snapping angrily at people, or in order to relieve my misery, as engaging in sinful pleasures. So despite the general situation, I would be personally less likely to be saved if I lived the religious life.”
It is not clear how strong this response is, but at least it is consistent with accepting the general teaching of the Church on vocations. Likewise, the unbeliever can modify his response to the following: “Even if Christianity is true, it seems false to me, and from my point of view, choosing to believe it would be choosing to believe something false. The Bible makes clear that people rejecting the light and choosing darkness are doing evil, so that would mean God wouldn’t be pleased by this kind of behavior. So choosing to believe would make me less likely to go to heaven, even given that Christianity is true.”
Once again, it is not clear how strong this response is, but it is consistent with the claims of Christianity, and no less reasonable than the response of the single Catholic to the argument regarding vocations.
Scott Alexander, in the comment quoted previously, is dissatisfied with such arguments because they do not provide a general answer that would apply in all possible circumstances (e.g. if you were guaranteed that God did not object to your choosing to believe something you think to be false), and it seems to him that he personally would want to reject the wager in all circumstances. He concludes that his desire to reject it is objectively unreasonable. However, he does this under the assumption that the value of getting to heaven and avoiding hell is actually infinite. As we have seen, it is not infinite in the way that matters. However, he also assumes in his comment that the probability of Christianity is astronomically low. If this were correct, then since the value of salvation is not numerically infinite, it would be right to reject the wager in all circumstances. But since it is not correct to assign such a low probability, this does not follow.
The implication is that it is not possible to give a reasonable response to the wager which implies that it would never be reasonable to accept it. Likewise, the implication of the possible responses is that it is not possible to propose the wager in a form which ought to be compelling to anyone who is reasonable and under all circumstances. In this sense, Scott Alexander is right to suppose that his desire to reject the wager under all possible circumstances is irrational. Real life is complicated, and in real life a person could reasonably accept such a wager under certain circumstances, and a person could reasonably reject such a wager under certain circumstances.