I am slowly making my way through Geoffrey West's book Scale (2017). I am finally getting into his discussion of cites and how we might think about them. He makes this interesting observation:

This may seem obvious, but the emphasis of those who think about cities, such as planners, architects, economists, politicians, and policy makers, is primarily focused on their physicality rather than on the people who inhabit them and how they interact with one another. It is all too often forgotten that the whole point of a city is to bring people together, to facilitate interaction, and thereby to create ideas and wealth, to enhance innovative thinking and encourage entrepreneurship and cultural activity by taking advantage of the extraordinary opportunities that the diversity of a great city offers. This is the magic formula that we discovered ten thousand years ago when we inadvertently began the process of urbanization. Its unintended consequences have resulted in an exponentially increasing population whose quality of life and standard of living have on the average also been increasing. ~ 252.

Geoffrey then goes on to define a city as follows:

Cities are emergent complex adaptive social network systems resulting from the continuous interactions among their inhabitants, enhanced and facilitated by the feedback mechanisms provided by urban life. ~p 253

In discussions of city planning, the name Jane Jacobs often comes up. She helped to derail the plans of powerful New York city planner, Robert Moses, from putting an expressway through some culturally important neighborhoods of New York - Greenwich Village, SoHo and Little Italy. She also argued that it was the interactions in these neighborhoods that made them great and that putting a freeway through the center would destroy that.

West's definition of what a city is shares alot with the definition of what ecology is. Charles J. Krebs in his book Ecology (6th Ed, 2009) defines Ecology as follows:

Ecology is the scientific study of the interactions that determine the distribution and abundance of organisms. ~p 5

This definition suggest that we might be able to use some of the tools from ecology to understand the distribution and abundance of organisms in our cities. Those organisms include humans but also wildlife like these 2 deer that visited me last week when I was working outside.

I think it is worth reflecting on what makes a city great and whether it is a quality of the interactions that it affords, the quality of the physical infrastructure or some combination?

I don't think the great cities of this world are all made from the same cookie cutter. They can be great for different reasons. They can be larger or smaller in size. Some may be a hotbed of innovation where others may be a hotbed of cultural activity, community spirit, natural beauty, or educational attainment.