The Orthodoxy of Urbanism
Austin compares the two approaches to theories of language, Prescriptivism and Descriptivism:
"Prescriptivists are those who believe in objective, fixed rules to guide the usage of language; Descriptivists, on the other hand, seek to define a language by how people actually use it."
Planners have a tendency to develop a prescriptivist set of beliefs and approaches:
"Density, mixed-use development, and transit become components of an urbanist orthodoxy; a freeway through a vibrant neighborhood troubles the urban Prescriptivist in the same way an 'ain't' irks the English teacher."