Every desirable aspect of urbanism is achieved by building on the human scale, and conversely, every problem of urbanism is solved, eliminated or mitigated, by returning to the human scale of traditional cities. 
A human scaled city means it is a walkable city. People are healthier, happier, live longer due to more exercise, less noise, less pollution, less stress, less wasted time. A walkable town can function off grid and so is less dependent on faraway supply chains, fuel, etc.
A human scaled city is democratic. On foot everyone has to share the same streets. It fosters rather than alienates, a civil society. People desire the human scaled, the smaller the plot, the more fine grained the neighborhood, the more valuable it gets.
The human scale protects the city and the surrounding countryside from urban sprawl. Nature is now never more than a short walk away and equally accessible to everyone in the city. People who work in rural areas can access the city without passing through miles of urban debris.
