‘He has a seriously creepy vibe. I’m not going anywhere with him.’

‘This seems like phishing. I wouldn’t click that link.’

‘Something about this deal feels off. Walk away.’

When people say such things, they are not typically drawing conclusions from a chain of reasoning. The person who avoids getting in the stranger’s car is not thinking: ‘He displayed these three behavioural cues and, therefore, he poses a risk.’ The email isn’t flagged by going through an explicit checklist. The deal doesn’t announce its flaws through a formal audit. In each case, something is simply presented as having a certain character: the man as creepy, the email as fraudulent, the deal as suspect. And yet, acting on these intuitions seems not merely excusable but entirely reasonable .…