Fitts's Law
Movement time grows as targets get smaller and farther away.
Evidence: well established. We label every concept honestly, and say so when it's a teaching model. How we rate evidence.
Shrink Definition
Fitts's law describes how the time to reach a target depends on how far away it's and how big it is. Small, distant targets take longer to hit accurately than large, close ones. It's a remarkably reliable rule of movement, used everywhere from sports to designing buttons on a screen. It captures the built-in tradeoff between speed and precision in aiming.
Plain language
Reaching a small, far target takes longer than a big, near one.
Shrink Insight
The size and distance of a target set a hard limit on how fast you can hit it.
Why it matters
It gives a precise rule behind skilled movement and good design, from athletics to user interfaces. It grounds the speed-precision tradeoff in a testable law.
Common misunderstanding
People think practice can make any precise movement arbitrarily fast. There's a lawful limit set by target size and distance that training can't fully erase.
Shrink Perspective
Aiming has a math, and it favors big and near.
Shrink Reflection
Where could I make an important target bigger or closer?
Shrink Step
To move faster and more accurately, make key targets bigger or closer when you can.
Shrink Minute
Notice how much easier a large, near target is to hit than a small, far one.
Shrink Takeaway
Bigger and closer targets are faster to hit.
Medical boundary
This concept is educational and shouldn't be used to self-diagnose. It doesn't replace care from a licensed clinician. Symptoms, medication, and treatment decisions should be discussed with a qualified professional, and emergency symptoms require emergency care.
Evidence summary
A highly reliable, mathematically precise law of motor behavior confirmed across decades and settings.
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