Among those who believe the Bible is the word of God, those with more formal education are less likely to believe in human evolution than those with less education.

Democrats and Republicans differ in their beliefs that humans contribute to global warming. According to a Pew poll conducted in 2008, only 28 percent of Republicans, compared to 58 percent of Democrats, believe humans contribute to global warming (Pew Research Center 2008; Mooney 2012). Also noteworthy, this gap between Democrats and Republicans is smaller among non-college graduates than among college graduates. Among non-college graduates, 31 percent of Republicans, compared to 52 percent of Democrats, believe humans contribute to global warming, which is a difference of 21 percentage points. But among college graduates, only 19 percent of Republicans, compared to 75 percent of Democrats, believe humans contribute to global warming, which is a difference of 56 percentage points.

If you examine these numbers carefully, you will notice something else interesting about the difference between Republicans and Democrats. Among Democrats, education is positively related to the belief that humans contribute to global warming. That is, 52 percent of non-college educated Democrats believe humans contribute to global warming, and that percentage climbs to 75 among college-educated Democrats. The more education Democrats have, the more they tend to believe humans contribute to global warming.

In contrast, the relationship between education and the belief that humans contribute to global warming is negative among Republicans. Among non-college educated Republicans, 31 percent believe humans contribute to global warming, and that percentage declines to 19 percent among Republicans with a college education. Assuming the overwhelming majority of climate scientists are correct that humans contribute to global warming, the beliefs of Republicans deviate more from the scientific evidence with more education.

A similar result, where the beliefs of those who have more education deviate further from scientific consensus than do the beliefs of those who have less education, arises among those who believe the Bible is the word of God. We call this the “Bible-believers” effect.

The Bible-Believers Effect

Those who believe the Bible is the word of God (“Bible believers”) and those who don’t believe the Bible is the word of God (“Bible nonbelievers”) differ in their beliefs that humans evolved from earlier species of animals. Based on data from 2006 to 2012 in the General Social Survey (which is a nationally representative sample of American adults), 23 percent of those who believe the Bible is the word of God believe in human evolution, compared to 66 percent of those who don’t believe the Bible is the word of God.1 This gap in beliefs about human evolution increases with education: the gap is smaller for those with less education than for those with more education. For example, of those with less than a high school education, 31 percent of Bible believers and 56 percent of Bible nonbelievers believe in human evolution, which is a difference of 25 percentage points. But among those with graduate degrees, 10 percent of Bible believers and 79 percent of Bible nonbelievers believe in human evolution, which is a difference of 69 percentage points.

Figure 1 reveals the Bible-believer effect in greater detail. The top (solid) line in Figure 1 plots the percentage of Bible nonbelievers, at each level of educational attainment, who believe in human evolution. The bottom (dashed) line in Figure 1 plots the percentage of Bible believers, at each level of educational attainment, who believe in human evolution. As Figure 1 shows, education is positively related to belief in human evolution among Bible nonbelievers. That is, 56 percent of Bible nonbelievers without a high school education believe in human evolution, and that percentage climbs to 61, 68, 72, and 79 percent among Bible nonbelievers whose highest level of educational attainment is a high school degree, a junior college degree, a bachelor’s degree, and a graduate degree, respectively. The more education Bible nonbelievers have, the more they tend to believe in human evolution. In contrast, the relationship between education and belief in human evolution among Bible believers is the reverse. That is, among Bible believers, the relationship between education and belief in human evolution is negative. Among Bible believers with less than a high school education, 31 percent believe in human evolution, and that percentage declines to 23, 18, 21, and 10 percent of Bible believers whose highest level of educational attainment is a high school degree, a junior college degree, a bachelor’s degree, and a graduate degree, respectively. In other words, Bible believers’ views about human evolution deviate more from the scientific evidence with more education.

The Bible-believers effect also arises when the belief the universe began with a huge explosion (the big bang) is substituted for the belief in human evolution. Belief in the big bang increases with education among Bible nonbelievers but decreases with education among Bible believers.

Figure 1: Percent of Bible nonbelievers and Bible believers who believe in human evolution for each level of educational attainment. Figure 1: Percent of Bible nonbelievers and Bible believers who believe in human evolution for each level of educational attainment.

What Accounts for the Bible-Believers Effect?

The General Social Survey (GSS) data reveal several factors that are not the cause of the Bible-believers effect. The Bible-believers effect is not due to a relative lack of scientific literacy, in general, among highly educated Bible believers. For example, highly educated Bible believers are more likely than less highly educated Bible believers to know basic scientific facts concerning such things as viruses, radioactivity, and genetics. Highly educated Bible believers only repudiate highly selected scientific facts such as those concerning human evolution and the big bang theory.

The Bible-believers effect is also not due to a relative lack of appreciation of the scientific method by highly educated Bible believers. That is, highly educated Bible believers are more likely, than less highly educated Bible believers, to understand the scientific method.

The Bible-believers effect is also not due to a relative deficit among highly educated Bible believers in general reasoning skills. Highly educated Bible believers have better general reasoning skills than less highly educated Bible believers. Nor are highly educated Bible believers more likely to accept pseudoscientific beliefs, such as astrology, than less highly educated bible believers. For example, 48 percent of Bible believers who have less than a high school education believe astrology is not at all scientific, compared to 61, 68, 79 and 83 percent of those whose highest level of educational attainment is a high school degree, a junior college education, a bachelor’s degree, and a graduate degree, respectively. Such a pattern of results would not arise if highly educated Bible believers were generally less skeptical than less highly educated Bible believers.

So the Bible-believers effect is not due to a relative deficit in general knowledge of scientific facts or the scientific method, cognitive skills, or pseudoscientific skepticism among highly educated Bible believers. But although these potential causes of the Bible-believers effect can be convincingly eliminated, what is the cause is less clear. Several potential explanations for the Bible-believers effect are plausible.

Strength of Religious Beliefs: The Bible-believers effect may be a consequence of the strength of religious beliefs and practices because highly educated Bible believers have stronger core religious beliefs and practices than do less highly educated Bible believers. For example, the GSS data set reveals that highly educated Bible believers pray more, attend religious services more, and report stronger religious affiliations than do less highly educated Bible believers. It is not clear why education is positively related to religious commitment among Bible believers, but given this relationship, it could account for the Bible-believers effect. The stronger a person’s commitment to religion (i.e., the more strongly the person holds core religious beliefs and the more frequently the person engages in religious practices) the more likely the person is to deny scientific facts (such as human evolution and the big bang theory) that conflict with the person’s strongly held religious beliefs (cf. Kahan et al. 2012).

Counterarguments: Mooney (2012) proposed a potential explanation for why highly educated Republicans are less likely to believe humans contribute to global warming than are less highly educated Republicans. Translated from that context to the context of Bible believers and human evolution, Mooney’s explanation is the following. Compared to less well educated Bible believers, more highly educated Bible believers better understand arguments used to deny human evolution and are, therefore, better able to justify their beliefs in the face of scientific evidence to the contrary. We are all susceptible to confirmation biases and the selective interpretation of evidence. For example, we tend to be less critical of evidence that supports our views and, conversely, more motivated than is justified to identify flaws in evidence that opposes our views (Lord et al. 1979). The cognitive skills needed to perform such self-serving assessments likely improve with education. That is, the more years of education a person has, the more skilled that person is in defending his or her beliefs when they are challenged.

Need for Consistency: Compared to the less well educated, those who are more highly educated may have a greater need for consistency in their beliefs (and a better understanding that belief in the Bible as the word of God is inconsistent with belief in human evolution). If they have a greater need for consistency of beliefs, those who are better educated would be more self-motivated than those who are less highly educated to reject human evolution and therefore more motivated (and not just better able) to employ self-serving assessments of evidence.

Over Confidence: Perhaps education breeds confidence in a person’s opinions regardless of their relationship to fact; if so, the more a person believes he or she knows the answers, the less likely that person is to be persuaded by conflicting evidence.

Implications

According to the GSS data, only slightly more than half of American adults (52 percent) believe in human evolution. Who among the 48 percent of evolution deniers is most open to changing their minds? We might hope those who are highly educated are (a) less committed to false beliefs, (b) more intellectually capable of understanding evidence that conflicts with their beliefs, and (c) more persuaded by rational argument than are those who are less highly educated, and hence more open to changing their beliefs.

But if any of the preceding hypotheses about the cause of the Bible-believers effect is correct, the Bible believers who are most open to changing their beliefs about human evolution are those who are least, rather than most, highly educated. Whether the Bible-believers effect arises because years of education and strength of religious convictions are correlated, because the highly educated are best at making counterarguments, because the highly educated have the greatest need for consistency, or because the highly educated are most overconfident, highly educated Bible believers would be less likely to change their mistaken views about human evolution than less highly educated Bible believers. In other words, if any of the preceding explanations of the Bible-believers effect is correct, highly educated Bible believers not only deny human evolution more but are also more committed to denying human evolution than are less highly educated Bible believers.

An implication is that the argument for human evolution may be a particularly hard sell among highly educated Bible believers. In addition, a debate about human evolution that presents both sides of the argument may be counterproductive among Bible believers regardless of educational level. In particular, a debate that includes the argument that the Bible conflicts with human evolution and that highlights counterarguments to human evolution, might serve more to entrench mistaken beliefs than to weaken them among Bible believers of all educational levels (Lord et al. 1979). That is, a debate that presents both sides of the argument for human evolution could heighten awareness of how core beliefs about the Bible conflict with belief in human evolution and present both counterarguments to and evidence against human evolution, and thereby enhance the motivation and ability to defend one’s mistaken beliefs regardless of educational level. This is just one of many reasons skeptics might object to presenting either creationism or intelligent design alongside evolution in the science curriculum of public schools.

Conclusions

Education tends to be positively correlated with knowledge. The greater a person’s level of formal education, the greater is his or her knowledge and acceptance of scientific facts, in general. But among Republicans, education is negatively correlated with the belief that humans contribute to global warming. Republicans who are most highly educated are those who most often deny humans’ role in global warming, which is contrary to scientific consensus. In addition, education is negatively correlated with belief in human evolution, among those who believe the Bible is the word of God. Of those who believe the Bible is the word of God, the most highly educated are most likely to deny human evolution, which is contrary to scientific consensus. These results suggest that rational, evidence-based arguments in support of scientific facts may be less effective in correcting the false beliefs of the highly educated than in correcting the false beliefs of the less highly educated, when those facts conflict with core conservative values.

Note

1. The results are fr­om a sample of 4,084 respondents. Subsequent results are also fr­om the General Social Survey.

Acknowledgments

The authors thank Kendrick Frazier, George Potts, Rob Roberts, and Doug Russell for their helpful comments.

References

Kahan, D.M., E. Peters, M. Wittlin, et al. 2012. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Climate Change 2: 732–735.

Lord, C., L. Ross, and M. Lepper. 1979. Biased assimilation and attitude polarization: The effects of prior theories on subsequently considered evidence. Journal of Personality and Social Psychology 37: 2098–2109.

Mooney, C. 2012. The Republican Brain: The Science of Why They Deny Science—and Reality. New York: Wiley.

Pew Research Center for the People and the Press. 2008. A deeper partisan divide over global warming. Washington, D.C. Online at http://www.people-press.org/2008/05/08/a-deeper-partisan-divide-over-global-warming/.