Jonah: “Darwinianism is not a successful evolutionary adaptation. Mormonism is.” Well, it’s news to me—and will be to a lot of Mormons, I am sure—that a Mormon can’t accept modern biology (“Darwinianism”).

The nugget of truth in your reader’s comment is, that very-committed religious types tend to have more kids than agnostics and atheists. You need to watch that “tend.” Some deeply religious types foreswear procreation: the R.C. priesthood most obviously, and that American sect—was it the Shakers?—that eventually… died out. Still, if it’s procreation you want, then yes, the Mormons, Haredim, evangelical Christians, devout R.C.s, and Muslim fundamentalists are your best bet. And if you want to live in a world full of various kinds of fundies, I guess that’s great news. I’m sure they will all get on really, really well together.

The deeper truth is that the universe and its laws don’t much care what happens to us. If modern biology is a true account of the world; and if accepting that truth tends to make you un-procreative; so that eventually the people holding a true account of the world die out; well, that’s too bad. To put it another way, if believing in false things—and Mormons, Haredim, evangelicals, and Wahhabists can’t all be guardians of the truth, since they have basic metaphysical disagreements with each other—makes you philoprogenitive, then falsehood will triumph at last, and truth be forgotten. There is no reason why this shouldn’t, or couldn’t, happen. The Poincaré Conjecture has turned out to be true, but the cosmos went on pretty well for several billion years without anyone knowing it.

Personally, I’d prefer to believe, like the poet that

The truth is great, and shall prevail,
When none cares whether it prevail or not.

…but that’s likely just a temperamental foible of mine, devoid of cosmic significance.