Law of Similarity

The human eye tends to perceive similar elements in a design as a complete picture, shape, or group, even if those elements are separated.

The human eye tends to perceive similar elements in a design as a complete picture, shape, or group, even if those elements are separated.
The human eye tends to perceive similar elements in a design as a complete picture, shape, or group, even if those elements are separated.

Takeaways

Elements that are visually similar will be perceived as related.
Color, shape, and size, orientation and movement can signal that elements belong to the same group and likely share a common meaning or functionality.
Ensure that links and navigation systems are visually differentiated from normal text elements.

Origins

The principles of grouping (or Gestalt laws of grouping) are a set of principles in psychology, first proposed by Gestalt psychologists to account for the observation that humans naturally perceive objects as organized patterns and objects, a principle known as Prägnanz. Gestalt psychologists argued that these principles exist because the mind has an innate disposition to perceive patterns in the stimulus based on certain rules. These principles are organized into five categories: Proximity, Similarity, Continuity, Closure, and Connectedness.

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