Architecture is distinguished from building by its public aspect, It is part of a complex human community, the city, whose social structure must go beyond familial relationships. Such relationships between otherwise unrelated people are traditionally built on cosmological models with which everyone can identify. The models are expressed in terms of number and geometry.
The form of the city and the design of its component structures are also governed by such models. This presentation reviews some of these models and illustrates their appearance in cities and architectural designs past and present.