"The point of cities is multiplicity of choice"First of all, I'll repeat here with my own words a disclaimer that the author offers in the book: this work is about cities in America (think NYC, Atlanta, or St. Louis) and its arguments are not applicable or intended for towns and smaller communities.Even though I'm no expert in urbanism, sociology or architecture I was left with the impression that this book must be a classic and an absolute gem on these subjects. This is a meticulous book.The author definitely had spent an enormous amount of time observing cities and people in cities before writing this book. And that contributes to the empirical, incremental nature of her thought, as opposed to "ivory tower" urbanists, who planned cities from clerk desks and college rooms (something that ran wild in post-WW2 America).One of the main themes of Mrs. Jacobs is the necessity to create conditions for diversity in cities, everything else being hugely impacted by this single factor. You want to have neighborhoods that have a mix of people from different backgrounds and occupations (this guarantees, for example, that streets don't all go empty at 6 o'clock, et cetera). Diversity also impacts the economic health of a place, and attracts residents and visitors to interact in a more complete way.The book mentions countless things that, to the uninitiated, may appear at first simple, such as preferring smaller vs larger blocks, as the former are inherently more attractive to pedestrians and therefore more conducive to business activity and safety.There's a lot of criticism for the planners of housing projects that focused on sterile "green" spaces as if a park magically makes communities more livable while ignoring much more important aspects such as access to business activities, walkability and safety. These planners the author changes with the fault of planning, in the abstract, poorly thought places that real people live in reality.There's also much criticism about the many ways in which city planning, sometimes intentionally and sometimes not, promoted racial discrimination in America.Remarkably little of the book is dedicated to the critique of cars (it is there, but much less than I expected).This book was written over 60 years ago, at a time when American planners were mostly engaged in work that is very much contrary to the notions of this book and time, in my opinion, has validated her ideas and made them more relevant than ever.This is a tremendous work, full of provocative humor and from a truly independent thinker who wrote about cities in a humanistic way.