“Fancy the expensive New Year’s party?”

“If everyone else does.”

“I’m easy.”

“Same.”

That is four votes for a party nobody has said they want. One person books it because delay might disappoint the others. The others transfer money because objecting now feels stingy. By midnight, £320 has purchased warm prosecco, a queue for the toilets and enough suppressed resentment to heat a bungalow.

Later, somebody says they would have preferred chips in the quiet pub. Two others immediately agree. The organiser is furious: “Why didn’t anyone say?” Nobody asks why the organiser did not say either.

The Abilene trap has no mastermind. It runs on considerate guesses. Each person mistakes the others’ public compliance for private enthusiasm, then contributes more compliance as evidence. A show of hands can make this worse because the first raised hand changes the cost of keeping yours down.

Sometimes compromise is simply compromise. Four different preferences produce the least objectionable option. Here the bizarre feature is that the supposed majority preference belongs to nobody.

The same group plans summer. A message arrives: “Beach house again?” Three thumbs-up emojis appear. The fourth person types, “Only if people actually want it,” deletes the sentence, and adds a fourth thumb.

Behavioural principles

Behavioural ideas at play in this post

Short, plain-English explanations of the principles behind this post, with links to related books and examples in the archive.