Unity (sometimes also called Harmony) refers to the connecting of parts of a work of art, creating a feeling of peace and a sense of completeness.
Unity is created when harmonious elements have a logical relationship or progression. In some way they work together and complement one another.
Too much unity can create a feeling of monotony in an art piece while not enough unity or harmony can look chaotic, like an ill-fitting and meaningless assortment of elements.
J. Paul Getty Museum, Principles of Design.
Flyeschool, Principles of Design, Harmony.
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