Who Shall Inherit the Earth?

Everyone keeps saying that Islam is the world's fastest-growing religion. It has become a truism. Apparently, though, the matter is not all that clear; and our view is probably distorted by an unusually fast growth rate for Islam in Europe specifically.

The world's fastest growing major world religion, proportionate to present size, actually seems to be Zoroastrianism. But Zoroastrianism is unlikely to become a major world player any time soon.

So you have to restrict Islam's claim to "among the four or so largest faiths," or something like that. But note too, that is only proportionate to present size. In absolute numbers, the world's fastest-growing religion is Christianity.

If current trends continue, Christianity will continue to increase its share of world population. Islam is growing too; the big losers are tribal religions and atheism. The world is growing more religious.

And here's another wrinkle: Islam's growth is almost all through the human reproductive process; in terms of conversions, Christianity is well ahead (though Zoroastrianism leads here too).

Can we assume Muslims will continue to far outbreed Christians indefinitely? It seems more likely that, as the Muslim world, currently a lot poorer than the Christian world, develops, Muslims will follow trends elsewhere and start having fewer children.

So the prospect of Islam inheriting the world does not seem to be all that likely, long term.