#mental-model #bias #rationality
# [[Epistemic status]]
#shower-thought
# Hindsight Bias
false confidence on predicting events
"i knew it"
>Past events will always look less random than they were (it is called the hindsight bias).
>~ [[Nassim Taleb|Taleb]]
>Speaking of "hindsight bias" is just the nontechnical way of saying that humans do not rigorously separate forward and backward messages, allowing forward messages to be contaminated by backward ones.
~ [[Eliezer Yudkowsky]]
## Conservation of expected evidence
The cure to hindsight bias is to ensure you keep the same predictions after the event occurring.
>**Conservation of Expected Evidence**: The expectation of the posterior probability, after viewing the evidence, must equal the prior probability.
$P(H) = P(H, E) + P(H, E)$
$P(H) = P(HE × P(E) + PH-E) × P(-E)$
Therefore, for every expectation of evidence, there is an equal and opposite
expectation of counterevidence.
~ [[Eliezer Yudkowsky]]