“First, to foster lively and interesting streets. Second, to make the fabric of these streets as continuous a network as possible throughout a district of potential sub-city size and power. Third, to use parks and squares and public buildings as part of this street fabric; use them to intensify and knit together the fabric’s complexity and multiple use. Fourth, to emphasize the functional identity of areas large enough to work as districts … Nothing is more helpless than a city street alone, when its problems exceed its powers.”