4F. Phases of life:

The concept of generation relative to humans is helpful as long we realize its limitations. For cities there are only perceived generations. Older cities do not necessarily become elderly and functionally fade away. Instead, what we relate to human generations are the life stages of a single, growing, global organism.

In the growth section, I compared and highlighted the differing growth patterns of Philadelphia and Perth. Even when relative time is taken into consideration and one compares the young, dominant, booming Philadelphia of the 18th century with contemporary Perth, differences abound. Due to technological advancement, cities exhibit extreme generation gaps. Perth is physically much larger than Philadelphia was at the same age.

Not only do cities increase in size across generations, but the rate of growth also accelerates. Cities are growing larger, faster. This undermines the universal utility of common models of generation, as offspring normally resemble their parents in terms of size and growth.

Globally, from the world’s first city to present day, the life of cities resemble that of fungi: Although points of focus relocate, the collective whole continues to spread. As it spreads, growth capabilities are enhanced by the existing foundation thus, the observation of an accelerated growth rate.

Across generations, or the phases of the urban organism’s life, the physical size and population of focal cities increase by a certain magnitude. Unfortunately, I cannot yet offer a basic of mathematical equation for magnitude of generational change. Due to the size and complexity of the issue, such precise measurements may not be possible. Should one exist, I suspect the raw data have already been collected via economic research.