What Is Hindsight Bias

The same bars, looked at from two dates

Hindsight bias is an ending, once known, making the beginning look as if it pointed there all along. Gold closed at 3416.46 on 28 August 2025. Thirty-seven trading days later, on 20 October, it printed 4381.38, 965 dollars and 28 percent higher. On 28 August the chart showed nothing about those thirty-seven days, because they had not happened. On 20 October the chart shows every one of them, and the run looks like it was always coming. The bars up to 28 August are the same on both dates. What changed is that the ending is now on the screen, and the eye reads the beginning through it.

A maze, from above and from inside

Picture a maze. Seen from above, after someone has walked it, the way through is drawn in gold and it is obvious; anyone can trace it with a finger and wonder how the walker ever hesitated. Seen from inside, at the time, it was walls, and every junction was a choice made without knowing what lay past the corner. Hindsight is the view from above. It is a real view of a real maze, and it is available only after the walking is done. The trade was made from inside, by someone who could not see the gold line, and it has to be judged as a choice made there.

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