Laws of Perception · cognitive-bias
Cognitive Load
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The total mental effort a task demands. Some load is intrinsic to the task; the rest — decoding layout, parsing jargon, hunting for buttons — is extraneous, and every unit of it comes out of the user's budget for the actual goal.
Where it comes from
John Sweller developed cognitive load theory in 1988 while studying why some math teaching failed: learners' working memory was maxed out by HOW material was presented, leaving nothing for the material itself. His split of intrinsic vs. extraneous load became a design compass — you can't reduce the task's essential difficulty, but every ounce of interface friction is yours to delete.
Origin: Sweller's 1988 cognitive load theory
In the wild
- Tax-filing software
Products like tax filers win by absorbing brutal intrinsic complexity into one question at a time.
- Airline booking
Seat maps show price + position visually; the text-table version of the same data burns the user's budget on decoding.
- Settings screens
Search inside settings exists because a hundred toggles exceed anyone's willingness to scan.
Further reading
Don't just read it — feel it.
Play the 3-minute game and let your own reactions prove the law.
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