1) The document presents a future town concept called "Last Life" that the author envisions building in the sky by 2150 due to environmental pollution and resource depletion on Earth.
2) It investigates ancient, present, and future town examples - Memphis, Egypt; Shinjuku, Japan; and Lusail City, Qatar - to inform the design of Last Life. Key lessons include modifying Memphis' laws to protect all citizens and businesses in Last Life.
3) Shinjuku demonstrates earthquake-resistant building technology that could help Last Life withstand weather changes, though it has high costs. Prioritizing citizen safety over costs is recommended for Last Life.