1. What is a city?
“A city is a social form in which people physically live in close proximity to one another.” -- Timothy Keller, “Center Church”, p135.
“A permanent & densely settled place with administratively defined boundaries whose members work primarily on non-agricultural tasks. Historically, city-dwellers have been a small proportion of humanity overall, but following two centuries of unprecedented and rapid urbanization, roughly one-half the world’s population now lives in cities. Most U.S. states use a minimum between 1500-5,000 people to define an urban area.”
-- en.wikipedia.org/wiki/City