Zoning for diversity As production becomes increasingly clean and knowledge-based, as our urban economies tip dramatically to service industries, as racism and ethnic animosities ebb, and as the model of mixed use becomes more and more persuasive and visible, cities are in a position to dramatically rethink zoning as a medium for leveraging and usefully complicating difference, rather than simply isolating it. Michael Sorkin, 20 Minutes in Manhattan zoningrace
The greatest flaw in city zoning Raskin, in his essay on variety, suggested that the greatest flaw in city zoning is that it permits monotony. I think this is correct. Perhaps the next greatest flaw is that it ignores scale of use, where this is an important consideration, or confuses it with kind of use. Jane Jacobs, The Death and Life of Great American Cities zoningmonotonyscale
The air doesn't know about zoning boundaries Work uses suggest another bugaboo: reeking smokestacks and flying ash. Of course reeking smokestacks and flying ash are harmful, but it does not follow that intensive city manufacturing (most of which produces no such nasty by-products) or other work uses must be segregated from dwellings. Indeed, the notion that reek or fumes are to be combated by zoning and land-sorting classifications at all is ridiculous. The air doesn’t know about zoning boundaries. Regulations specifically aimed at the smoke or the reek itself are to the point. Jane Jacobs, The Death and Life of Great American Cities zoningregulationsseparation
Paths, edges, districts, nodes, landmarks The contents of the city's images which are referable to physical forms can conveniently be classified into five types of elements: paths, edges, districts, nodes, and landmarks. Paths are the channels along which the observer customarily, occasionally, or potentially moved. Edges are the linear elements not used or considered as paths by the observer. They are the boundaries. Districts are the medium-to-large sections of the city, conceived of as having two-dimensional extent. Nodes are points, the strategic spots in a city into which an observer can enter, and which are the intensive foci to and from which they are traveling. Landmarks are another type of point-reference, but in this case the observer does not enter within them, they are external. They are usually a rather simply defined physical object: building, sign, store, or mountain. Kevin Lynch, The Image of the City City districtsAs a kind of gateway cities