The point is not that people are foolish. The point is that trust is expensive, and we economise on it like everything else. The textbook treats trust as a preference to be revealed. In practice it is a story we tell ourselves after the fact. Put a number on trust and it becomes a target; put a target on it and the number stops meaning what it meant. We describe the departure from the model as an error. We might equally describe the model as a hopeful guess about us.
What it gets right
There is a version of this essay that ends with a policy prescription. This is not that version; the mechanism is interesting enough on its own. A pattern this consistent is not a character flaw. It is a design feature, and design features can be worked with. Every one of us runs the same shortcut, and every one of us believes we are the exception. Notice how rarely anyone is argued out of the second opinion, and how often they are simply moved past it by a change in circumstance.
It is tempting to call this irrational. It is more useful to ask what it is for. The honest conclusion is uncomfortable for reformers: people are not waiting to be corrected. Nobody sets out to be governed by the second opinion, yet it shapes an astonishing share of the ordinary day. If you want to see trust at work, watch a queue form where there is no reason for one.
