an excellent framing. structuring these laws by the brain's two operating systems—system 1 (fast, intuitive) and system 2 (slow, analytical)—clarifies why they work.
this aligns with the principle of designing for how people actually think.
here is the reordered list based on that cognitive framework.
system 1 (fast thinking): perception & intuition
(these laws engage our automatic, intuitive, and emotional brain. interfaces that align with these principles feel effortless and "right" because they don't require conscious thought.)
- laws of perception (the gestalt principles)
- law of prägnanz: our brain’s automatic simplification of complex images.
- law of proximity: seeing close-together items as a group.
- law of similarity: seeing similar-looking items as a group.
- law of common region: seeing items in the same boundary as a group.
- law of uniform connectedness: seeing visually linked items as a group.
- laws of reaction & bias
- aesthetic-usability effect: the immediate gut feeling that beautiful = usable.
- doherty threshold: the subconscious reaction to system speed (fast feels good, slow feels bad).
- fitts’s law: the automatic, practiced motor skills used to point and click on targets.
- jakob’s law: the intuitive reliance on familiar patterns from other experiences.
- mental model: the automatic application of what we think we know about a system.
- peak-end rule: forming a memory based on an emotional shortcut, not a logical average.
- von restorff effect: the automatic capture of our attention by a visually distinct item.
- laws of behavioral impulse
- paradox of the active user: the impulse to act first and read later (or never).
- goal-gradient effect: the automatic increase in motivation as a goal gets closer.
- flow: the state where system 1 is so fully engaged that system 2 is silent.
system 2 (slow thinking): analysis & deliberation
(these laws relate to our conscious, analytical mind. they are engaged when we need to learn, compare, or solve problems. the designer’s goal is often to minimize the user's system 2 load.)
- laws of cognitive load & memory
- working memory: the limited mental workspace system 2 uses for its operations.
- miller’s law: the known capacity limit (~7 items) of this workspace.
- cognitive load: the total effort demanded from system 2 to use an interface.
- chunking: the conscious strategy of breaking down complex information so system 2 can process it.
- selective attention: the deliberate act of focusing our limited cognitive resources.
- zeigarnik effect: the memory of an incomplete task that prods system 2 to return to it.
- laws of choice & complexity
- hick’s law: the direct relationship between the number of choices and the time system 2 needs to decide.
- choice overload: the state of paralysis when system 2 is overwhelmed by too many choices.
- tesler’s law: the fact that every system has irreducible complexity that either the designer or the user's system 2 must handle.
- serial position effect: the tendency to remember first/last items, which system 2 can use as a shortcut for analysis.
meta-principles: strategic design heuristics
(these are not laws of user cognition but are system 2 principles for the designer. they guide strategic decisions about how to build the system in the first place.)
- occam’s razor: a rule for designers: choose the simplest solution.
- pareto principle: a rule for designers: focus 80% of effort on the 20% of the system that delivers the most value.
- postel’s law: a rule for designers: create systems that are tolerant of a user's imprecise (system 1) inputs.
- parkinson’s law: a rule for designers: be mindful that work expands to fill available time.
- cognitive bias: the designer's conscious awareness of the automatic (system 1) biases in both themselves and their users.