GURPS Space: Carrying Capacity

[SenorPez]

Does GURPS Space consider Earth to be an Affinity 10 planet? It's obvious it's Habitability 8, but in order to have a sufficient carrying capacity to account for the world's population (10 B) it would have to have Very Abundant resources to get to Affinity 10.

Or am I missing something in the Carrying Capacity calculation?

Base Carrying Capacity, TL8: 10 M
Affinity Modifier, Affinity 10: 1000
Affinity Modifier, Affinity 9: 500
Diameter: 1

10 M * 1000 * 1^2 = 10 B (Enough!)
10 M * 500 * 1^2 = 5 B (2.5 B short!)

If that's the case, I need to reconsider my "Average" resource planet. I modeled its mining activity based on Earth, tweaked for lower tectonics and volcanic activity. But if Earth is Very Abundant, that Average planet would be far less rich in minerals than I've envisioned.

[Humabout]

Originally Posted by SenorPez

Does GURPS Space consider Earth to be an Affinity 10 planet? It's obvious it's Habitability 8, but in order to have a sufficient carrying capacity to account for the world's population (10 B) it would have to have Very Abundant resources to get to Affinity 10.

Or am I missing something in the Carrying Capacity calculation?

Base Carrying Capacity, TL8: 10 M
Affinity Modifier, Affinity 10: 1000
Affinity Modifier, Affinity 9: 500
Diameter: 1

10 M * 1000 * 1^2 = 10 B (Enough!)
10 M * 500 * 1^2 = 5 B (2.5 B short!)

If that's the case, I need to reconsider my "Average" resource planet. I modeled its mining activity based on Earth, tweaked for lower tectonics and volcanic activity. But if Earth is Very Abundant, that Average planet would be far less rich in minerals than I've envisioned.

You assume the Earth can support its current population (7.53 B) indefinitely. The jury is out as to whether or not that is possible. Furthermore, SPACE, p. 92, states :

Originally Posted by GURPS Space, p. 92

On the other hand, a high-tech society can also exceed the carrying capacity, but only by using world resources in a way that can’t be sustained indefinitely. Such a society will be in trouble within a few generations, unless it can improve the carrying capacity of its world.

...

At TL5 and above, a homeworld’s population can vary widely from its carrying capacity. Select a population as needed, or roll 2d. Multiply the carrying capacity by 10, and divide the result by the die roll to get the world’s population.

Finally, GURPS Space was written twelve years ago. Science has come a long way since then. It'd be understandable if the ideas in GURPS Space are out of date. That's actually why Jon F. Zeigler has been writing a new star system generation system called Architect of Worlds based on more modern planetary science research.

So with all of that said, I'd be more likely to believe that Earth hass Average Resources...like most other planets in existence...and expect either a population crash, mass emigration, or the plane to be stripped of all resources and then a massive population crash/extinction.

[AlexanderHowl]

I agree. The Earth is a TL8 society at 3x its carrying capacity (and merrily breeding itself to 4x). This is why we are experience global warming, mass extinctions, crushing poverty, etc.

If the Earth population was 2 billion people, the average income would be $31,000 (GURPS) or $62,000 (2018$). In effect, the average standard of living on Earth would be slightly better than that of the USA. Imagine if the average person in Ethiopia or Bangledesh earned $31,000 (2018$) rather than $900 and you start to understand the difference. The global GDP would be around $62 trillion (GURPS) or $124 trillion (2018$) because there would be less inefficiencies in the global economic system.

[whswhs]

Originally Posted by AlexanderHowl

If the Earth population was 2 billion people, the average income would be $31,000 (GURPS) or $62,000 (2018$). In effect, the average standard of living on Earth would be slightly better than that of the USA. Imagine if the average person in Ethiopia or Bangledesh earned $31,000 (2018$) rather than $900 and you start to understand the difference. The global GDP would be around $62 trillion (GURPS) or $124 trillion (2018$) because there would be less inefficiencies in the global economic system.

Only if you assume that the economic output remained the same while nearly 75% of the labor force disappeared. At best that's a partial equilibrium solution.

[hal]

The Malthusians always seem to figure that mankind will hit its limit with respect to resource use, food supply and other factors. Funny thing is, every time they've predicted the end of the world, it hasn't quite hit.

There is more to the equation than simple math, simple economics, or even simple resource allocation and and distribution. Throughout history, we've seen what happens when a political class institutes itself in a manner that becomes parasitic. The more you burden the working class in the form of taxation, and then force them to live by laws regarding "living within your means", the more the tax burdens cause the population being taxed, forced to exchange services in lieu of taxes, food production etc - begin to shrink.

Expecting a 2% population growth is simply not viable in the long run and history does not show it to be true. Sure, it CAN happen under the right circumstances - but it almost inevitably slows down. The population of England over the period of several hundred years resulted in a growth rate of .3% per year. Not 2% - but .3 percent.

Couple this with the knowledge that medieval England's ruling elite (the roughly 2%) were able to tax the rural peasants some nearly 50 to 55% and even in some instances 60% of their production (what we'd call income) were in large part, living as parasites. What HOST can anyone point to, survive the loss of 50 to 60% of its energy and nutrients and survive as a healthy specimen?

So - take a hard look at the taxes being paid by today's young. Add all of the Income Taxes taken by your government(s) in all its levels (Federal, state, Local) and add to that the gasoline taxes levied on your gas that you have to use if you own a vehicle. Then toss in all of the taxes you pay on your cable and phone and internet use. Throw in your property taxes, your fees that you pay to the government for any given thing (car inspections, etc).

Want to be that you'd be very close to the 45% to 50% mark? Some European nations are definitively at the 50% mark.

Now compare/contrast the birth rates (children per woman) and note that in some countries, the rate is 1.7 to 1.9 (Western Civilizations) and then make the sobering observation that to have a zero percent growth rate, we need a reproduction rate of 2.1 children per woman. One to replace the mother, one to replace the father, and .1 children to account for fatalities before the age of adulthood, disease, fertility issues, and even the decision to not get married or have children at all.

So, 2% annual growth without taking into account something as silly as government parasitical behaviors, is kind of like forgetting some basic math functions when adding numbers together that are large in scope.

Do I expect the Earth to grow warmer over time? Sure. Is it man-influenced Global Warming? I tend to doubt that. If our sun is 20% brighter today than it was when it first started burning, that implies that it brightens up on its own, whether mankind is present or not. Do we have living records of weather patterns over the last few hundred years? Yup. Do we have historical records of dry/wet hot/cold seasons over time from ancient past periods (we call them petrified wood) and yes, it appears that what we see today has happened in the past. Even California's dry/wet cycles are historical and predate an industrial mankind. <shrug>

In the end? The Malthusian alarmists would have us believe that we're heading to perdition if we don't abstain from sinning against Mother Earth. So far their record of being right tends to be dismally low (from a statistical standpoint).

As has been pointed out repeatedly, the GURPS WEALTH rules just don't model reality all too well. Trying to utilize those rules for future modeling is going to be inherently fraught with inaccuracies.

True story: My father purchased unimproved land back in the mid-50's. He told us all that for what he paid for the land, he could have purchased a GOOD car. After paying property taxes on the land over the years, when he finally sold it (still unimproved), guess what. The money he made on the sale (after capital gains taxes) was enough to buy him a higher end car.

So - take it for what it is worth, the economics portrayed in GURPS is not something I'd use for a doctoral thesis.

[whswhs]

Originally Posted by AlexanderHowl

I agree. The Earth is a TL8 society at 3x its carrying capacity (and merrily breeding itself to 4x). This is why we are experience global warming, mass extinctions, crushing poverty, etc.

I don't think that last part can be said to be really accurate. Up until the substantial economic hit of the pandemic, at least, Earth was experiencing a sustained worldwide decrease in absolute poverty and specifically in hunger: Not merely in proportion of the population experiencing either but in absolute numbers doing so, even as total population climbed. There's not much point in saying "A is the underlying cause of B" if B is not in fact present.

The Simon-Ehrlich wager might also be relevant.

[AlexanderHowl]

How would you explain all of the scale, scope, and speed of the human-caused environmental problems? It is not that human civilization cannot deal with them through investment and technology, it is that they are occurring in the first place that is the sign of exceeding carrying capacity. If we were not exceeding the carrying capacity, we would not be dealing with human-caused environmental problems.

We can also use economics to determine overpopulation. The global per capita nominal income was ~$10,000 in 2017, which is less than one-third of the per capita income suggested for TL8 in Space, which us pretty close to what it should be for a population of 7.5 billion. If Earth possessed Affinity 9, it would have a carrying capacity of 5 billion people and the per capita income would be $23,250. If Earth possessed Affinity 10, it would have a carrying capacity of 10 billion people and the per capita income would be $43,400.

[Rupert]

Originally Posted by AlexanderHowl

We can also use economics to determine overpopulation. The global per capita nominal income was ~$10,000 in 2017, which is less than one-third of the per capita income suggested for TL8 in Space, which us pretty close to what it should be for a population of 7.5 billion. If Earth possessed Affinity 9, it would have a carrying capacity of 5 billion people and the per capita income would be $23,250. If Earth possessed Affinity 10, it would have a carrying capacity of 10 billion people and the per capita income would be $43,400.

Not all of Earth's population is living at TL8.

[malloyd]

Originally Posted by whswhs

I don't think that last part can be said to be really accurate. Up until the substantial economic hit of the pandemic, at least, Earth was experiencing a sustained worldwide decrease in absolute poverty and specifically in hunger: Not merely in proportion of the population experiencing either but in absolute numbers doing so, even as total population climbed. There's not much point in saying "A is the underlying cause of B" if B is not in fact present.

In many places that is because the average age of the population is going up - i.e. more of it is in the productive part of their lives. In fact the average number of children per woman globally has dropped down to something pretty close to 2 (i.e. replacement) for new mothers - it's 2.4 even for all women, down from about 2.8 as recently as 20 years ago. The population is still increasing only because there were *fewer people* in the past, so the number of people in the older age cohorts is low for the numbers in the younger ones - that is only because the population was recently not in equilibrium.

Earth's population dynamics for the last century or so are definitely not the equilibrium case that ecological carrying capacity assumes. The debate is over whether that's a sign the carrying capacity increased, resulting an S curve step function, a temporary perturbation that will result in a post J curve crash, or something in between.

[David Johnston2]

Originally Posted by whswhs

I don't think that last part can be said to be really accurate. Up until the substantial economic hit of the pandemic, at least, Earth was experiencing a sustained worldwide decrease in absolute poverty and specifically in hunger: Not merely in proportion of the population experiencing either but in absolute numbers doing so, even as total population climbed. There's not much point in saying "A is the underlying cause of B" if B is not in fact present.

The Simon-Ehrlich wager might also be relevant.

It's worth remembering that Gurps Space offers a trade-off. If you exceed carrying capacity then you can either settle for a lower typical income or you can barrel on until your civilization collapses in resource depletion and ecological catastrophe. Of course that latter outcome can be averted if you manage to make it to a higher tech level before the hammer comes down.