Did you guess the correct answer? Well, there is no right and wrong answer, but if you thought it might be because the man would turn up at her sister’s funeral, you’ve apparently ‘thought like a psychopath’.

• The second scenario is equally as unsettling: “A runaway trolley is about to run over and kill five people and you are standing on a footbridge next to a large stranger; your body is too light to stop the train, but if you push the stranger onto the tracks, killing him, you will save the five people. Would you push the man?”

If you chose to push the man, despite saving more people, apparently it’s still the answer that most aligns with a psychopathic thought process.

It’s important to note that these scenarios absolutely do not diagnose psychopathy – and the team at the Columbia Business School points this out themselves.

“Although the study does not resolve the ethical debate, it points to a flaw in the widely-adopted use of sacrificial dilemmas to identify optimal moral judgment,” said Daniel Bartels, one of the study authors at Columbia Business School.

“These methods fail to distinguish between people who endorse utilitarian moral choices because of underlying emotional deficits (like those captured by our measures of psychopathy and Machiavellianism) and those who endorse them out of genuine concern for the welfare of others.”