Dr. Harry Roy, a professor of biology at Rensselaer Polytechnic Institute in New York, saw my talk on evolution, religion, and science, and societal dysfunction, which proposed not only that antievolutionism in most countries is motivated by religion (duh!), but religion itself is promoted by societal dysfunction, so that those societies with higher levels of income inequality, child mortality, incarceration, and lower levels of health care (all embodied in Greg Paul’s “Successful Societies Scale”) are the most religious. My suggestion was that if we want to promote acceptance of evolution, in the end we have to build healthier societies.

In that talk, I showed a slide from Greg Paul’s work documenting a pronounced (and statistically significant) negative correlation between the degree of religiosity of 17 Western nations (and Japan) and their “success” as measured by the SSS. This was supported by other studies showing a striking positive relationship between income inequality (as measured by the Gini Index) and each of 12 separate measures of religiosity. A tentative conclusion is that people are more religious when their societies fail to give them the support or feeling of well-being that, for example, is enjoyed by inhabitants of countries like Sweden and Denmark.

Anyway, Harry found some relevant data in the United States, crunched the numbers, and did a statistical analysis. He left comments and a link to the analysis, after my post. And he’s kindly done a bit more analysis and allowed me to reproduce it here. What he found is precisely the same relationship among states (using the HDI) as I found among countries: American states with lower HDIs are more religious.

First, a portrait of American religiosity taken from a 2009 Gallup poll:

As we know, the south is really religious (just go there if you doubt that!), and the northeast and west coast states much less so.

And below is a national map of the Human Development Index (HDI) from Wikipedia. This index is a measure of societal well being that differs from the “Successful Societies Scale” (SSS) that I used in my talk at Harvard. The HDI uses a set of traits that differ from those used in the SSS: the former amalgamates three traits (life expectancy, education, and income), while the latter combines 25 traits, including corruption, income disparity, child mortality, access to medical care, suicide rates, and so on. Unlike the SSS, under which the U.S. ranks very low among first-world nations, the HDI places the U.S. at the top when the index is not adjusted for inequality among residents, but falls much lower when adjusted for inequality (see the Wikipedia article on the HDI at link above). The disparity may be due to the inclusion of income inequality in the adjusted HDI; income inequality is highly positively correlated with religiosity across 71 nations.

The south is not so great here, the northeast (and two states on the west coast) are better. That suggests a relationship between religiosity and well being as measured by the HDI.

After crunching the data, Dr. Roy produced this correlation between the religiosity of the 50 states and their ranking on the HDI:

As you see, we have the same negative relationship between well-being and religiosity that we saw for different countries of the West. The correlation here is r= – 0.66897, and the probability (“p”) that this correlation would arise by chance is p = 0.00000012. (A value of p less than 0.05 is conventionally used to show a significant relationship.) This relationship, then, is not only striking but very highly significant in a statistical sense. Harry put a least-squares regression line through the data; its slope is also highly significant.

Why the correlation? Again, it could mean—but I am not pushing this interpretation as dogma—that people tend to either become more religious or retain a historical religiosity in areas where they are not very well off. There may also be ethnic differences that contribute to this (the population of blacks in America is concentrated in the south, for instance, and educational attainment is lower in general), but education itself is likely negatively correlated with indices of well being, and poverty is a component of both the HDI and SSS. Although I’m not a Marxist, Marx may have gotten it right when he said, “Religion is the sigh of the oppressed creature, the heart of a heartless world, and the soul of soulless conditions. It is the opium of the people.”

Finally, here’s another figure, which I’ve reproduced before, on the correlation between poverty and religiosity:



