Common fate is another of the gestalt principles, and states that objects that are closer to each other or grouped in some way comparative to the overall set seem to be together, on a common path, or associated more closely than other design elements.
In this illustration, I started with a line of identical circles, evenly spaced. As the story progresses, the line of circles breaks into two even lines, creating two distinct groups. In the third part of the story, some of the circles go off on their own, and some of the circle pairs start to travel together, but none are a part of the original lines anymore.
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