Rhythm refers to any movement characterized by a patterned recurrence of elements or motifs at regular or irregular intervals. […] Rhythm incorporates the fundamental notion of repetition as a device to organize forms and spaces in architecture.
Francis D. K. Ching
Rhythm is a state of equilibrium which proceeds either from symmetries, simple or complex, or from delicate balancings. Rhythm is an equation; Equalization (symmetry, repetition) (Egyptian and Hindoo temples); compensation (movement of contrary parts) (the Acropolis at Athens); modulation (the development of an original plastic invention) (Santa Sophia). So many reactions, differing in the main for every individual, in spite of the unity of aim which gives the rhythm, and the state of equilibrium. So we get the astonishing diversity found in great epochs, a diversity which is the result of architectural principle and not of the play of decoration.
Le Corbusier
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