Proportion is a central principle of architectural theory and an important connection between mathematics and art. It is the visual effect of the relationship of the various objects and spaces that make up a structure to one another and to the whole. These relationships are often governed by multiples of a standard unit of length known as a "module".[1]
Proportion in architecture was discussed by Vitruvius, Leon Battista Alberti, Andrea Palladio, and Le Corbusier among others.