Death and science: the existential underpinnings of belief in intelligent design and discomfort with evolution

Abstract

The present research examined the psychological motives underlying widespread support for intelligent design theory (IDT), a purportedly scientific theory that lacks any scientific evidence; and antagonism toward evolutionary theory (ET), a theory supported by a large body of scientific evidence. We tested whether these attitudes are influenced by IDT's provision of an explanation of life's origins that better addresses existential concerns than ET. In four studies, existential threat (induced via reminders of participants' own mortality) increased acceptance of IDT and/or rejection of ET, regardless of participants' religion, religiosity, educational background, or preexisting attitude toward evolution. Effects were reversed by teaching participants that naturalism can be a source of existential meaning (Study 4), and among natural-science students for whom ET may already provide existential meaning (Study 5). These reversals suggest that the effect of heightened mortality awareness on attitudes toward ET and IDT is due to a desire to find greater meaning and purpose in science when existential threats are activated.

Figure 1. Effects of mortality salience (MS) on liking of Behe and belief in intelligent design theory (IDT), and liking of Dawkins and belief in evolutionary theory (ET), Study 1.

Note. Values are based on standard scores; means for each scale were computed by standardizing each of the six author-theory items that the scale comprised, around their common mean, and taking the mean of the resulting z-scores. Because the two scales were centered around different means, values on the two scales (Dawkins-ET and Behe-IDT) cannot be directly compared to each other. Based on a t-test, the difference between the control and MS conditions on Behe-IDT was significant, p<.05. Error bars represent the standard error of the mean. *p<.05.

Figure 2. Effects of MS on liking of Behe and belief in IDT, and liking of Dawkins and belief in ET, Study 2.

Note. Values are based on standard scores; means for each scale were computed by standardizing each of the six author-theory items that the scale comprised, around their common mean, and taking the mean of the resulting z-scores. Because the two scales were centered around different means, values on the two scales (Dawkins-ET and Behe-IDT) cannot be directly compared to each other. The overall interaction, which emerged from a mixed-measures analysis of variance (ANOVA), and the difference between the control and MS conditions on Dawkins-ET, based on a t-test, was significant, p<.05. Error bars represent the standard error of the mean. *p<.05.

Figure 3. Effects of MS on liking of Behe and belief in IDT, and liking of Dawkins and belief in ET, Study 3.

Note. Values are based on standard scores; means for each scale were computed by standardizing each of the six author-theory items that the scale comprised, around their common mean, and taking the mean of the resulting z-scores. Because the two scales were centered around different means, values on the two scales (Dawkins-ET and Behe-IDT) cannot be directly compared to each other. The overall interaction, which emerged from a between-subjects ANOVA, and the difference between the control and MS conditions, based on a t-test on Dawkins-ET, were significant, p<.05. Error bars represent the standard error of the mean. *p<.05.

Figure 4. Effects of MS on liking of Behe and belief in IDT, and liking of Dawkins and belief in ET, for participants who did not read Sagan's excerpt about naturalism (Panel A) and those who did (Panel B), Study 4.

Note. Values are based on standard scores; means for each scale were computed by standardizing each of the six author-theory items that the scale comprised, around their common mean, and taking the mean of the resulting z-scores. Because the two scales were centered around different means, values on the two scales (Dawkins-ET and Behe-IDT) cannot be directly compared to each other. The overall three-way interaction, based on a between-subjects ANOVA, and, in Panel B, the two-way interaction and the difference between the control and MS conditions, based on a between-subjects ANOVA and a t-test on Behe-IDT, respectively, were significant, ps<.05. Error bars represent the standard error of the mean. *p<.05.

Figure 5. Effects of MS on liking of Behe and belief in IDT, and liking of Dawkins and belief in ET, in a sample of natural science students, Study 5.

Note . Values are based on standard scores; means for each scale were computed by standardizing each of the six author-theory items that the scale comprised, around their common mean, and taking the mean of the resulting z-scores. Because the two scales were centered around different means, values on the two scales (Dawkins-ET and Behe-IDT) cannot be directly compared to each other. The overall interaction, based on a mixed-measures ANOVA, and the main effects on Dawkins-ET and Behe-IDT, based on t-tests, were significant, ps<.05 one-tailed. Error bars represent the standard error of the mean. *p<.05 one-tailed.