There are some very smart converts to Catholicism (as well as some very smart cradle Catholics). What’s the appeal? If Catholicism is gravely mistaken, why can’t they see through it? In my observation, there are at least four factors–which doesn’t mean every bright convert exemplifies all four motivations:
1. Catholicism has a very rich, wide-ranging intellectual and artistic heritage that’s naturally appealing to the religious-minded intelligentsia.
2. Many Catholic intellectuals are Thomists. Thomism presents a much less inviting target for atheists than a Bible-centered faith. Thomism is abstract and abstruse. Most atheists know nothing or next to nothing about Thomism, so they have no line of attack. If, by contrast, you have a Bible-centered faith, that instantly gives them hundreds of openings since there’s a cottage industry of stock objections to Scripture.
3. Catholicism requires converts to make fewer accommodations to unfashionable beliefs. Take the facile way Bishop Barron relegates “problem passages” in the OT to pious fiction or allegory. They can leave “embarrassing” beliefs behind while retaining “respectable” beliefs they share in common with their secular counterparts. A Bible-centered faith doesn’t have the same loopholes. It must stand and fight.
4. Finally, if you’re smart enough, you can defend almost anything, and you may revel the challenge. Here I think there’s an element of divine irony or divine justice. High IQ confers a completive advantage, but that’s offset by the fact that it can also be a snare or a source of self-deception. The temptation to flex his ingenuity plays to his intellectual pride. Coming up with clever, erudite defenses of Roman Catholicism is an opportunity to indulge in self-flattering showmanship. I hasten to add that it’s by no means confined to Catholicism. There’s a special kind of folly that bright guys are prey to. Their strength is their weakness.
Someone might object that there’s a certain tension between #4 and #’s 2-3. However, I think all these motivations are observable. People can be inconsistent. Psychology isn’t logicality. Moreover, as I said at the outset, a convert doesn’t have to check all four boxes.