Origins
In 1910, psychologist Max Wertheimer had an insight when he observed a series of lights
flashing on and off at a railroad crossing. It was similar to how the lights encircling a movie theater
marquee flash on and off. To the observer, it appears as if a single light moves around the marquee, traveling
from bulb to bulb, when in reality it’s a series of bulbs turning on and off and the lights don’t move it all.
This observation led to a set of descriptive principles about how we visually perceive objects. These
principles sit at the heart of nearly everything we do graphically as designers.
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