The mind that evolved for small groups and immediate dangers is now asked to manage a pension. It does its best. What looks like risk from the outside is usually something simpler from the inside: tiredness, a deadline, a wish not to look foolish. Consider the borrowed book. It is a small thing, and small things are where habits live. 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.
The ordinary case
The mind that evolved for small groups and immediate dangers is now asked to manage a pension. It does its best. We describe the departure from the model as an error. We might equally describe the model as a hopeful guess about us. In the studies we have, the effect is modest, reliable and almost entirely ignored by the people it describes. The evidence here is thinner than the confident commentary suggests, and the honest position is a shrug with a direction of travel.
