Everyone knows population-increase grows cities and crowds freeways. As a result freeways get wider and cities get bigger.

Everyone knows that if city dwellers want bigger cars or houses cities and freeways grow even if the population doesn't.

Harder to grasp is that city growth requires more square miles of ocean and farm land to feed its dwellers. Cities need more water to flush its toilets and water its lawns. Farms need more land and water to feed city people. Cities need more energy to heat homes, run transport, and produce goods and services.

Cites already consume 75% of the resources humankind consumes. Farmland is finite. Oil reservoirs, aquifers, and rain are finite. Places to put waste are finite. Mined resources, like soils and iron are finite.

There is a whole web of life from bacteria to polar bears that share this finite environment. When humans usurp their space and resources they are extinguished. Loss of diversity threatens the eco system.

When there are relatively few cities and a lot of unallocated global resources, city growth appears to have no limits. But when the support for all these cities equals the environment's abilities to produce, one city must compete with another for scarce resources. Eventually the competition turns into disenfranchisement and conflict.

Conflict consumes resources. This leaves less resources to support cities. Which increases scarcity. Which increases competition. Which increases conflict. Which diverts more resources away from supporting cities. The circular process causes civilization to experience a death spiral?

Two possible approaches to keep scarcity of goods and services from triggering collapse of civilization. One increases global carrying capacity with technological efficiency and substitution. The other constrains total human footprint.

Many people think these dangers can be avoided by a combination of technological expansion and population stabilization. However, even with a cessation of population growth technological expansion is facing a very large task.

First, because we don't know how close the current human footprint is to the globe's limits. Some would say we have overshot them at present technology and are depleting fish stocks, oil reservoirs, aquifers, and damaging climate.

And second total human footprint would still continue to grow because 80% of today's global population, the poor, consume at a rate of 1/8 to 1/16 of that consumed by the 20%, who are wealthy. We should expect these have-nots to increase their consumption. If they doubled that consumption every twenty five years, It would take a century or more for them to catch up with the haves and it would quadruple the total human footprint and the technologist's challenge.

In addition to the poor's increase in consumption the haves will increase their wellbeing. The goods and services required by even a constant population will likely double every 20 years for centuries.

If we are counting on technology to protect us from the vagaries of scarcity, it will have to double global production of goods and services (with fixed land and less dense energy) every 20 years for centuries.

Any technological shortcomings will have to be addressed by constraints on total human footprint. At first this might be viewed as capping the excesses of the rich. However, if improved health care increases longevity that increases footprint and it has nothing to do with excesses.

Since total human footprint is the product of population times per capita consumption, any improvement in wellbeing will have to be matched with reductions in population. Even an improvement in healthcare requires a decrease in population.

If we expect a doubling of human footprint every twenty years, and technology fails to keep up then the prevention of scarcity must be addressed with a halving of the population every 20 years.

Rapid population decline (RPD) appears to be "the" path to a viable future for our kids, our nation, humankind, and our ecosystem.

Rapid population decline (RPD) occurs only when deaths greatly exceed births. The three mechanisms for having deaths exceed births are:
     1) deprivation (starvation or disease,)
     2) genocide, and or
     3) birth rates far below two per woman.

The challenge that confronts us is, "Can we engineer a future with lesser amounts of RPD caused by deprivation and genocide and more RPD caused by lower births?" (1) ---

--- continued SKIL note 63)---

--------notes below----
(1) Many answers to the following questions justify a shift in emphasis from current proposals that address visible problems (eco destruction, resource exhaustion and social inequity) to RPD proposals that produce civilization viability.

1. What is the carrying capacity that is divided between humans and other species?
   
2. How much and how fast can carrying capacity drop?
   
3. When will carrying capacity drop?
4. If billions are living hand to mouth on a dollar
   or two a day, how fast can a doubling of food costs (demand over supply) put billions on a death diet?  
5. How long can/will the rich keep the poor from starvation using redistribution?
6. When it is obvious that redistribution will not satisfy the starving hordes and inhibit their social conflict, how long will it be before the rich or powerful resolve their desperation with genocide?
7. How fast can a lower birthrate reduce the population? ( will be addressed in SKIL note 63)