Cognitive Bias
A cognitive bias is a consistent, predictable deviation from sound judgment. It isn't random error or stupidity — everyone makes the same ones, which is exactly why they can be studied and named. They arise because the brain leans on fast heuristics instead of slow, exhaustive analysis: shortcuts that are right often enough to be worth it, but that misfire in regular ways.[1] Many map directly onto logical fallacies — the bias is the mental pull, the fallacy is the faulty argument it produces. A few of the best-documented are below.
Drill down
Confirmation Bias
The tendency to seek, notice, and remember evidence that fits what we already believe — and to discount what doesn't.
Anchoring Effect
Relying too heavily on the first number or fact you encounter, which drags later judgments toward it.
Availability Heuristic
Judging how likely something is by how easily examples come to mind — so vivid, recent events feel more common than they are.
Related concepts
Related docs
hierarchy prerequisite related