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The body · The matrix
Which body each law presumes
31 of the 38 laws change result when any of the 6 dimensions changes. Law by law that is invisible; together it becomes the map. Tap a name to open the law, or a column heading to open the dimension.
18 checked against a study· 16 deduced from the mechanism· 4 do not talk about people
- measured, and the study is in the bibliography
- there is literature on this, and I have not checked it yet
- my own reasoning from the mechanism; nobody measured it
- I checked all six and found no variation; nobody tested it on purpose
- says nothing about people — it describes the work, not who uses it
| Law | a channel how it comes in and goes out | a place where they use it | an era when they measured | a history what it has already seen | a culture where they measured | a condition how they are right now |
|---|---|---|---|---|---|---|
| Fitts’s lawAn important target is a big target, close to where the hand already is.Open the law → | a channel, measured, and the study is in the bibliography, hand and eye | a place, my own reasoning from the mechanism; nobody measured it | an era, measured, and the study is in the bibliography | no | no | no |
| Hick–Hyman lawCut what does not change the decision. Splitting into steps does not reduce the cost of choosing, it spreads it.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Doherty thresholdRespond in under 400 ms, even if only to say it is processing.Open the law → | no | a place, my own reasoning from the mechanism; nobody measured it | no | no | no | no |
| Cognitive load theoryAdd up everything the screen asks for at once, and take away half.Open the law → | no | no | an era, measured, and the study is in the bibliography | no | no | a condition, measured, and the study is in the bibliography |
| Miller’s lawGroup into blocks of up to four, and make the blocks contrast with each other.Open the law → | no | no | an era, measured, and the study is in the bibliography | no | no | no |
| Tesler’s lawComplexity does not disappear: decide whether it stays with you or with whoever uses it.Open the law → | a channel, says nothing about people — it describes the work, not who uses it | a place, says nothing about people — it describes the work, not who uses it | an era, says nothing about people — it describes the work, not who uses it | a history, says nothing about people — it describes the work, not who uses it | a culture, says nothing about people — it describes the work, not who uses it | a condition, says nothing about people — it describes the work, not who uses it |
| Parkinson’s lawGive effort a limit with deadlines and interim goals, real ones and not invented ones.Open the law → | no | no | no | no | no | a condition, my own reasoning from the mechanism; nobody measured it |
| Law of proximityWhat belongs to the same subject sits together; distance is already information.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Law of similarityThe same visual treatment means the same function, even if the elements are far from each other.Open the law → | a channel, measured, and the study is in the bibliography, eye | no | no | no | a culture, measured, and the study is in the bibliography | no |
| Law of common regionA shared border or background can group even against distance.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Law of uniform connectednessAn explicit line between two elements is usually enough, even against distance.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Law of PrägnanzIf the screen does not explain itself as a wireframe, colour is not going to fix it.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Salience biasHighlight one thing per screen. Two is already none.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Clustering illusionBefore presenting a pattern in the data, look for what refutes it.Open the law → | a channel, I checked all six and found no variation; nobody tested it on purpose | a place, I checked all six and found no variation; nobody tested it on purpose | an era, I checked all six and found no variation; nobody tested it on purpose | a history, I checked all six and found no variation; nobody tested it on purpose | a culture, I checked all six and found no variation; nobody tested it on purpose | a condition, I checked all six and found no variation; nobody tested it on purpose |
| Law of legibilityContrast, size and leading come before the choice of typeface.Open the law → | a channel, measured, and the study is in the bibliography, eye | a place, my own reasoning from the mechanism; nobody measured it | no | no | a culture, my own reasoning from the mechanism; nobody measured it | no |
| Law of visibilityIf it is essential, it is on screen. Hidden menus are for the secondary.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | a place, my own reasoning from the mechanism; nobody measured it | no | no | no | no |
| a channel, says nothing about people — it describes the work, not who uses it | a place, says nothing about people — it describes the work, not who uses it | an era, says nothing about people — it describes the work, not who uses it | a history, says nothing about people — it describes the work, not who uses it | a culture, says nothing about people — it describes the work, not who uses it | a condition, says nothing about people — it describes the work, not who uses it | |
| Aesthetic–usability effectDo not refine the aesthetics before validating the concept, the finish hides the defect.Open the law → | a channel, measured, and the study is in the bibliography, eye or ear | no | no | no | a culture, my own reasoning from the mechanism; nobody measured it | no |
| Flow stateRaise the difficulty at the same speed the person improves.Open the law → | no | no | no | no | no | a condition, measured, and the study is in the bibliography |
| Zeigarnik effectSignal the end of each step; an open task keeps taking up space.Open the law → | no | no | no | no | no | a condition, measured, and the study is in the bibliography |
| Negativity biasHandle the error, the empty state and the rejection first: that is where the return on effort is highest.Open the law → | no | no | no | no | no | a condition, measured, and the study is in the bibliography |
| Temporal discountingIf the value takes time to appear, deliver pieces of it along the way.Open the law → | no | no | an era, measured, and the study is in the bibliography | no | no | a condition, measured, and the study is in the bibliography |
| Jakob’s lawBreak the pattern only when you can say why.Open the law → | no | no | no | a history, my own reasoning from the mechanism; nobody measured it | no | no |
| Scarcity biasOnly show scarcity when it is true, and say what the limit is.Open the law → | no | no | no | no | no | a condition, my own reasoning from the mechanism; nobody measured it |
| Availability heuristicFix the worst case before the average case: it is the vivid that stays in memory.Open the law → | no | no | no | a history, my own reasoning from the mechanism; nobody measured it | no | no |
| Peak–end ruleInvest in the high point and the ending; the middle is hardly remembered.Open the law → | no | no | an era, measured, and the study is in the bibliography | no | no | no |
| Von Restorff effectOne element different from the rest is remembered. Several different ones, none.Open the law → | a channel, my own reasoning from the mechanism; nobody measured it, eye | no | no | no | no | no |
| Serial position effectWhat needs to be remembered goes at the beginning or the end of the list.Open the law → | a channel, I checked all six and found no variation; nobody tested it on purpose | a place, I checked all six and found no variation; nobody tested it on purpose | an era, I checked all six and found no variation; nobody tested it on purpose | a history, I checked all six and found no variation; nobody tested it on purpose | a culture, I checked all six and found no variation; nobody tested it on purpose | a condition, I checked all six and found no variation; nobody tested it on purpose |
| Pareto principleFind the 20% that solve 80% and give them pride of place.Open the law → | a channel, says nothing about people — it describes the work, not who uses it | a place, says nothing about people — it describes the work, not who uses it | an era, says nothing about people — it describes the work, not who uses it | a history, says nothing about people — it describes the work, not who uses it | a culture, says nothing about people — it describes the work, not who uses it | a condition, says nothing about people — it describes the work, not who uses it |
| Choice-supportive biasConfirm the choice, but leave the way back open.Open the law → | no | no | an era, measured, and the study is in the bibliography | no | no | no |
| Endowment effectDon’t take away what you have already given. If you must take it away, warn first and say what goes in its place.Open the law → | no | no | no | no | a culture, measured, and the study is in the bibliography | no |
| Anchoring biasThe first number becomes the ruler. Choose carefully which one you show first.Open the law → | no | no | no | no | a culture, measured, and the study is in the bibliography | a condition, my own reasoning from the mechanism; nobody measured it |
| Social proofA real social number helps. An invented one destroys trust in the rest of the screen.Open the law → | no | no | no | no | a culture, measured, and the study is in the bibliography | no |
| Mere-exposure effectRepeat the pattern until it becomes comfort and stop before it becomes irritation.Open the law → | no | no | no | a history, my own reasoning from the mechanism; nobody measured it | no | no |
| Illusion of transparencyYou are not the one who will use it. Test before concluding it is clear.Open the law → | a channel, I checked all six and found no variation; nobody tested it on purpose | a place, I checked all six and found no variation; nobody tested it on purpose | an era, I checked all six and found no variation; nobody tested it on purpose | a history, I checked all six and found no variation; nobody tested it on purpose | a culture, I checked all six and found no variation; nobody tested it on purpose | a condition, I checked all six and found no variation; nobody tested it on purpose |
| Fundamental attribution errorWhen someone makes a mistake, investigate the flow before blaming the person.Open the law → | no | no | no | no | a culture, measured, and the study is in the bibliography | no |
| Flexibility and efficiency of useOffer the guided route and the shortcut, not a middle ground that serves neither.Open the law → | a channel, says nothing about people — it describes the work, not who uses it | a place, says nothing about people — it describes the work, not who uses it | an era, says nothing about people — it describes the work, not who uses it | a history, says nothing about people — it describes the work, not who uses it | a culture, says nothing about people — it describes the work, not who uses it | a condition, says nothing about people — it describes the work, not who uses it |
| Illusion of controlGive real control along with the feeling of control.Open the law → | no | no | no | no | a culture, measured, and the study is in the bibliography | no |
Does not vary, as far as anyone knows The mechanism is cognitive and I found no evidence that it changes with channel, place, era, history, culture or condition. These are the candidates to survive intact — and none of them was tested on purpose for it.
Not about people These four do not describe a person: they describe the work. Tesler says complexity does not vanish, it only changes sides. Occam says do not add what is not needed. Pareto observes a distribution. Two roads says who to design for. None of them claims anything about how someone perceives, remembers or decides — so their empty row here is not missing research, it is the answer.