There is a lot of conversations on this topic recently, and the answer is probably yes.  At the moment there are probably too many people, but once we are able to live in harmony with nature and each other, and especially once we start expanding beyond the Earth (as and when that ever happens), then the capacity for more people should be almost limitless.

If an each person stood in a 10 square foot / 1 square meter space, the entire human race would fit on the island of Jamaica with room to spare.  The limiting factor is therefore much more about resource availability/consumption than physical space.

The world’s population was half it’s current size only less than 55 years ago, and only 1/8th its size 220 years ago, so clearly human societies can exist perfectly well with far fewer people than currently exist. The difficulty is in the shrinkage, not in the fundamental population size.

If you conduct the thought experiment of weighing up the pros and cons of a population half the size of today, or twice the size, which would be better would seem to be an obvious choice. Technology and policy could help mitigate both scenarios, but fundamentally unending growth within a constrained environment is always going to tip in to disaster at some point.

The problems of population shrinkage are well documented, revolving around the working age to retired age population ratios causing financial disfunction, and epidemics of abandoned towns and villages, old age loneliness and declines in economic growth due to labour shortages amongst many other things. However what is seldom considered in the proffered doomsday scenarios is the human capacity for innovation and adaption. Innovation and adaption will be required, and will be forthcoming as populations become smaller as current projections forecast.

This is not an anti-human rant – humans are quite possible the only, or one of very few scientifically aware populations in the entire Milky Way galaxy, and therefore a tiny island of meaning in a mind-boggling large ocean of stars and solar systems. Brian Cox has a truly transcendental take on this. If we buy into this logic, then humanity is of cosmic importance, and its ability to survive, grow and thrive is paramount. Nor it is a criticism of natalist policies. Families should be supported and children brought up without wanting for food, warm shelter, education, healthcare and affection.

Medium term shrinkage in the human population is probably inevitable given current trends, and the, again well documented, underlying reasons behind those trends remaining in place. However it is not a phenomenon that is happening in isolation, and needs to be considered as part of much broader societal change. Two of the biggest are

1. AI. Artificial Intelligence has the capacity to change society in fundamental, and probably unknowable ways. It can be reasonably assumed however that it will replace a significant number of well paid jobs in a lot of industries. It also offers opportunities to tax companies in different ways to top up national coffers.
2. Robotics. Combined with AI, robotics offers potential solutions in manufacturing, service industries, and in caring for the old and infirm (and probably many other areas both considered and not yet even thought of).
3. Extended healthy life span. It’s been said that the first person to live to 200 years old may well have already been born. Clearly this will make current population projections redundant. Not only by the reduced number of natural deaths (for at least a time), but people would be much less concerned about balancing career and family, there would be time for both, potentially stabilising the population in the long term anyway.

A declining population will also potentially mitigate some existing problems (some of which are really existential in nature). These include

1. Aggressive expansionism. The issues associated with a shrinking population may make expansionist leaders think twice about invading others. Why expand into other territories if you have millions of empty houses in your own country? There will also be a problem of a lack of soldiers to wage that war (however see AI/automation). Of course it may go the other way, and wars of conquest maybe waged to distract a population from problems caused by its decline.
2. Climate change, bio-diversity, deforestation. Consider the size of these problem if the world population was to continue to grow as it has done in the last 50 years. It maybe that a population growth slow down will give us the breathing space to transition to a more sustainable relationship with our plant.
3. Inequality. Inequality is a complex subject with various takes on how much of problem it is. However what is clear is that billions of people look to the west with their cars and A/C and meat rich diets and want a piece of that. Is it fair to deny people that progress? The larger the population the bigger the impact is on the plant’s ability to absorb that resource consumption and emission production. Again, moving to more sustainable path would mitigate this problem.

As well as the potential mitigation of existing problems that will need to be overcome by competent and considered government policies (yes, the problem there is clear)

1. Dying towns and cities, and perhaps even countries. Management of such decline and the ability to let go of the emotional side of this, and turn some areas back to nature in a fruitful way will be needed
2. Labour shortages will have to be mitigated with robotics and AI. Policy and markets will need to redirect people into professions that are not suitable for automation.
3. Looking after the elderly. Again robotics and AI should be especially effective here. An AI helper will be more patient with someone suffering from dementia or memory problems than a person could ever be. It is quite possibly a solution to an epidemic of loneliness that is already haunting society.
4. GDP growth. Growth need to change from being an absolute measure for each country to a relative measure against a population. Growth in harmony with resource management should enable wellbeing for everyone.
5. Tax Revenue will shrink if tax if labour remains the predominant policy. This will clearly need to change such that taxes on things such as accrued wealth, property and a company profits are a bigger contributor. This will also require a society wide shift. Clearly capitalism works, because incentives drive almost all human behaviour, so coming up with a system that rewards the brightest and most productive people without leaving everyone else in the dirt will be a key challenge.  It should be noted that labour shortages beget an increase in the value of that labour which will help with this issue.
6. Old (and rich) people voting for old (and rich) people facing policies. Agreeing on what makes up the greater good, and then getting people on board with that will be tough. Unfortunately history suggests it will take a catastrophe of some kind (and there are no shortage of candidates) for a significant majority to pull together to that end.

Humanity has truly epic, cosmic even, possibilities. We just need to survive long enough to be in a position to achieve them.

MT