'Black and white' affects moral judgment

British scientists have discovered that seeing black and white objects can make people more judgmental when it comes to moral questions.

Psychologists at the University of Cambridge found that people who viewed information on a black and white background were less likely to see the grey area of a moral dilemma, while people who viewed information alongside other colours were more open-minded.

"We now find that judgment style can also be influenced by metaphors such as black-and-white thinking," said psychologist Simone Schnall, who did the study.

The study was broken into three parts. In the first section, 111 participants were asked to read the fictional story of Heinz – a poor man who stole cancer medicine for his sick wife because he couldn’t afford the treatment.

Each story was surrounded by a different coloured border: black-and-white checks, yellow and blue checks, and plain grey.

When the participants were asked to judge the morality of Heinz’s actions, it appeared the participants who viewed the story on a black-and-white background were more resolute in their opinions.

"People gave more polarised judgments when they saw some black-and-white checkered background that was in principle irrelevant and incidental," Schnall said.

In the second part, Schnall recruited 130 more volunteers and, using the same backgrounds, asked participants about the morality of different behaviours, such as smoking. Again, the people who saw the black-and-white background had stronger judgments.

In the third study, Schnall tested the metaphor of “the scales of justice”. She tested whether subtle “balance” cues would affect people’s judgment.

In one question, participants read a story about an athlete who gave blood for research on the condition he remained anonymous. But when a banned drug was found in his blood, he was banned from competing.

Some people viewed words printed normally, which had no impact on their opinions. Others saw words that were slightly tilted, which appeared to encourage stronger judgments about the fairness of the story.

The research is yet to be published in a scientific journal, however, the study authors say it adds to earlier research that shows symbols can influence how we behave.

Schnall suggests these examples could play out in real life. For example, reading a news story on a black-and-white page compared to a colourful one could impact how you judge the story’s content.