Gestalt is the theory that proposes that the brain's operational principle is holistic with self organizing tendencies. The whole is different then the sum of the parts. We have form-forming capabilities in our senses that recognizes first firgures and whole forms rather then individual parts that make up the entire visual.
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Emergence : This picture is of a dalmatian sniffing the ground under the shade of a tree. The dog is not immediately recognized by individual parts but is uncovered as a whole.
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Reification: The visual of shapes based on the negative space by which they are formed.
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Multistability: The presence of 2 or more images in one shape or form. Both may not always be visible at the same time.
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Invariance: When an object is changed in some way either by rotating, twisting, or morphing is but it's still recognized as the same shape.
PrägnanzLaw of closure: seeing a closed object based on just enough information
Law of similarity: the minds grouping of elements into collective totalities based on relationships like color, size, and form
Law of proximity: grouping of images based on spatial or temporal proximity
Law of symmetry: objects are perceived collectively based on symmetry
Law of continuity: continence of any pattern in the mind
Law of common fate: grouping of elements based on their direction of movement