Alternative name: “I would have known this bias”

Hindsight Bias – is when you know the outcome of some process and you are overconfident that you would have predicted it. Even if you would educate people that they have hindsight bias this doesn't change their overconfidence. This is connected to My-side bias.

Experiment. You ask people to predict the outcome of some unfamiliar historical event, in which there are four potential outcome (the real experiment was based on a conflict between Gurkhas and British in 1814). 1) Victory A, 2) Victory B, 3) Deadlock without peace, 4) Deadlock with peace. And you have five groups. One that you don't tell what outcome have happened. And four others you are telling each different version of what have happened. In the table below there are real answers on what they declared they would answer. I marked on red the highest number in each column. Result: if you are gonna be told the outcome you will think you would have predicted it.

Hindsight