Jesus Christ
Jesus Christ depicted as the good shepherd Wikimedia Commons

People see religious iconography in items ranging from grilled cheese to bird faeces and dogs' bottoms because they need moral justice, claims a new study.

The paper, published in the journal Cognition, explains that the psychological phenomenon known as "pareidolia" (of which the "man in the moon" is the most famous example) is enhanced by the presence of moral content.

In order to explain why people tend to see sacred images in inanimate objects, a team of researchers at New York University carried out three experiments during which a group of people was shown screens of scrambled letters and asked to indicate whether they believed each string formed a word.

Participants tended to identify "moral words" such as virtue, steal or God over "non-moral words".

"Over the course of three experiments, we found that participants correctly identified strings of letters as words more often when they formed moral words (69% accuracy) than when they formed non-moral words (65%)," the study said.

"This suggested that moral content gave a 'boost' to perceptually ambiguous stimuli — a shortcut to conscious awareness. We call this phenomenon the 'moral pop-out effect.'"

The study compared the moral pop-up effect to the feeling of hunger.

Think about how you experience food when you are hungry compared to when you are full. When you are hungry, food seems to "pop out" and capture your attention. But when you're full, food doesn't register as strongly and temptation doesn't emerge.

The moral pop-out effect: Enhanced perceptual awareness of morally relevant stimuli

In the moral domain, such "hunger" may take the form of a desire to redress injustice.

According to social psychologist Melvin J. Lerner, people have a fundamental need to believe that they live in a fair and orderly environment, in which good things happen to good people and bad things happen to bad people.

Dog's bottom Jesus
This image of a dog's bottom that bears a remarkable resemblance to depictions of Christ from the medieval period onwards, went viral online last year via Twitter

When people are faced with unjust outcomes, they tend to satiate their "moral hunger."

To verify the connection between the moral pop-out effect and moral hunger, the researchers carried out some follow-up experiments.

In one of them, people read two versions of a fake news story before being shown flashing words on a screen.

The two stories featured a murderer who was either arrested or not arrested.

If the murderer in the article was still at large, participants recognised moral words with greater accuracy (79%) than those who read about the murderer being brought to justice (71%).

Pareidolia episodes are often accompanied by reports of their interpetation as a sign of hope for a suffering individual or family.

"Moral concerns can alter a person's perceptual experience, and this may help explain why these apparitions seem to appear when they do," the study concluded.