Half as many people will not support half as many enterprises In a given geographical territory, half as many people will not support half as many such enterprises spaced at twice the distance. When distance inconvenience sets in, the small, the various and the personal wither away. Jane Jacobs, The Death and Life of Great American Cities densitydistancegeographybusinesseconomics
highdensityandovercrowding They hated both equally, in any case, and coupled them like ham and eggs, so that to this day housers and planners pop out the phrase as if it were one word, “highdensityandovercrowding.” Jane Jacobs, The Death and Life of Great American Cities densityurbanism
What's wrong with the rational model We Don’t Really Know the Goal When We Start We Usually Don’t Know the Decision Tree – We Discover It as We Go The Nodes Are Really Not Design Decisions, but Tentative Complete Designs The Goodness Function Cannot be Evaluated Incrementally The Desiderata and Their Weightings Keep Changing The Constraints Keep Changing Frederick P. Brooks, Jr., What's Wrong With This Model? Changing constraintsDeciding what to designThe situation talks back