Our planets capacity

F150 Top speed

The Ford F150 super crew has a top speed limited to about 175 km/hr. That is not to say you should drive at 175 km/hr, it is just to say it can be done. So it is with human population. Some bright light somewhere will have a plan for a 20 million person Ontario. Doing that would be reckless, in the same way driving at 175km / hr is reckless and idiotic.

There are no rewards or punishments only consequences.

Many estimates for a maximum human population for the planet earth fall in the range of 4 billion to 16 billion persons.

Maximum is not the same as optimal. The well-known study of Daily (Ref 1) include sufficient wealth, access to resources, universal human rights, preservation of biodiversity and cultural diversity, and support for intellectual, artistic and technological creativity estimated the optimal population size in the vicinity of 1.5 – 2 billion people.

Another study estimated considering a comfortable consumption based on European living standard and a sustainable use of natural resources, suggesting only 2 billion people as appropriate size (Ref 2 and 3).

References:

1: Daily, G. C., Ehrlich, A. H. & Ehrlich, P. R. Optimum human population size. Popul. Environ. A J. Interdiscip. Stud. 15, 469–475 (1994).
2: Pimentel, D., Harman, R., Pacenza, M., Pecarsky, J. & Pimentel, M. Pimentel, David, Natural Resources and an Optimum Human Population. Popul. Environ. 15, 347–369 (1994).
3: Pimentel, D. et al. Will Limited Land, Water, and Energy Control Human Population Numbers in the Future? Hum. Ecol. 38, 599–611 (2010).

For more reading on optimal population size

Economic Growth, it’s a drug too.

A crowd is not the sum of the individuals who compose it. Rather it is a species of animal, without language or real consciousness, born when they gather, dying when they depart. Gene Wolfe, “The Shadow of the Torturer” (1980) – Severian, Chapter 31

Orphan link

BBC article