If you have any doubts, keep these words, pulled from Glaeser's Triumph of the City, always close to you. Indeed, memorize them....

To understand our cities and what to do about them, we must hold on to these truths and dispatch harmful myths. We must discard the view that environmentalism means living around trees and that urbanites should always fight to preserve a city’s physical past. We must stop idolizing home ownership, which favors suburban tract homes over high-rise apartments, and stop romanticizing rural villages. We should eschew the simplistic view that better long-distance communication will reduce our desire and need to be near one another. Above all, we must free ourselves from our tendency to see cities as their buildings, and remember that the real city is made of flesh, not concrete.

The truthfulness of this is such that the most meaningful thing you can do as a human being is to become an urban planner. Those who become priests or preachers are only considering themselves; to become an urban planner (improving the efficiency of a city, solving the problems of congested spaces) is to consider others in the most radical way possible. The Jesus of our time will not offer us sermons but diagrams.