I have often observed and thought about how some religions (e.g. Mormons, evangelicals) have large families to grow their religious sects from within. In the long run this is perhaps more effective than recruiting new members. I also believe that there are certain genetic traits that drive some people to be more religious than others.
One doesn't have to be a mathematician to understand that if this form of population growth is effective, then our society should be increasing in religiosity rather than declining. I believe, however, the overall trend is downwards -- but maybe not for the Mormons and evangelicals. Maybe there is not enough data to measure yet, but for most of the Mormons and evangelicals I have known, their beliefs are strong.
I have known Mormon and evangelical engineers and geologists, for example, who seem to not be bothered about the conflict between science and religion. It's like their brains have two hard drives of knowledge -- one full of their religious learnings and the other with scientific data. I don't know how they process that conflict mentally.
Okay, the subject is stupidity and sometimes I have to shake my head at some of the stupidity of the religious beliefs of some faiths. Sarah Palin is not an intellectual for sure, but she epitomizes the populism of many of the believers. Maybe 500 years from now her genes and those like her will be more prevalent as America truly becomes a theocracy like Iran. Ha.
Okay, I'm just thinking out loud again. No comment necessary.