The first fundamental of successful city life: People must take a modicum of responsibility for each other even if they have no ties to each other. This is a lesson no one learns by being told. It is learned from the experience of having other people without ties of kinship or close friendship or formal responsibility to you take a modicum of responsibility for you.

Jane Jacobs (1916-2006) American-Canadian journalist, author, urban theorist, activist

The Death and Life of Great American Cities, Part 1, ch. 4 (1961)
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