People merge supernatural and scientific beliefs when reasoning with the unknown, study shows

The study, published in the June issue of Child Development, offers new insight into developmental learning.

"As children assimilate cultural concepts into their intuitive belief systems -- from God to atoms to evolution -- they engage in coexistence thinking," said Cristine Legare, assistant professor of psychology and lead author of the study. "When they merge supernatural and scientific explanations, they integrate them in a variety of predictable and universal ways."

Legare and her colleagues reviewed more than 30 studies on how people (ages 5-75) from various countries reason with three major existential questions: the origin of life, illness and death. They also conducted a study with 366 respondents in South Africa, where biomedical and traditional healing practices are both widely available.

As part of the study, Legare presented the respondents with a variety of stories about people who had AIDS. They were then asked to endorse or reject several biological and supernatural explanations for why the characters in the stories contracted the virus.

According to the findings, participants of all age groups agreed with biological explanations for at least one event. Yet supernatural explanations such as witchcraft were also frequently supported among children (ages 5 and up) and universally among adults.

Among the adult participants, only 26 percent believed the illness could be caused by either biology or witchcraft. And 38 percent split biological and scientific explanations into one theory. For example: "Witchcraft, which is mixed with evil spirits, and unprotected sex caused AIDS." However, 57 percent combined both witchcraft and biological explanations. For example: "A witch can put an HIV-infected person in your path."

Legare said the findings contradict the common assumption that supernatural beliefs dissipate with age and knowledge.

"The findings show supernatural explanations for topics of core concern to humans are pervasive across cultures," Legare said. "If anything, in both industrialized and developing countries, supernatural explanations are frequently endorsed more often among adults than younger children."

The results provide evidence that reasoning about supernatural phenomena is a fundamental and enduring aspect of human thinking, Legare said.

"The standard assumption that scientific and religious explanations compete should be re-evaluated in light of substantial psychological evidence," Legare said. "The data, which spans diverse cultural contexts across the lifespan, shows supernatural reasoning is not necessarily replaced with scientific explanations following gains in knowledge, education or technology."