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In other words, in economically skewed societies, both the rich and the poor are more religious. In fact, they found that, for nearly all of the measures of religiosity, when societies are more unequal, the richer people become more religious than the poorer people (this association was positive for all 12 measures of religiosity and was statistically significant for four).
This last finding is important because it bears on two hypotheses about why unequal societies are more religious. The first, called the “deprivation theory,” is that in economically unequal societies, poorer folks turn to religion for reassurance and comfort. This is certainly the hypothesis I believed before I read this paper. The second hypothesis, which is the authors’ theory, is called the “relative power theory.” This holds that as societies become more economically unequal, richer people become more religious so they can disseminate religion to those who aren’t so fortunate.
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Their two findings from this analysis are:
“Increases in inequality in one year predict substantial gains in religiosity in the next,” while “past values of religiosity do not predict future values of inequality.” In other words, the correlation between religiosity and inequality is driven by the former responding to the latter, and not the other way around. Unequal incomes lead to societies becoming more religious.
“Holding inequality constant, gains in per-capita GDP are estimated to depress subsequent levels of aggregate religiosity.” In other words, increasing the average economic well being of people makes them less religious.
http://whyevolutionistrue.wordpress.com/2011/07/21/why-is-economic-inquality-associated-with-religiosity/Link to the paper (abstract only, but maybe some here can get full access:
http://onlinelibrary.wiley.com/doi/10.1111/j.1540-6237.2011.00777.x/abstract )
Jerry Coyne (the blogger) seems unconvinced that there is good evidence that rich people encourage the poor the be religious, as a whole (there are certainly some who encourage other to be religious so they themselves can
get rich, eg Pat Robertson, but that's a bit different). But it is interesting that the analysis over time points to inequality encouraging religiosity.