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Q. What is meant by progress?

A. Human progress in the last few centuries has included the following.

All these things are dependent on the material wealth of society. People can dispute about how divide the wealth, but there has to be wealth to divide. Here are some of the questions that have led some people believe this progress can't continue and some answers to the worries.

Q. Can the world grow enough food for 15 billion people?

A. Yes, it can, and with present technology. With better technology, probably a lot more. Biotechnology based on molecular genetics is just beginning to be applied to agriculture.

Q. Isn't the world running out of energy.

A. No. Nuclear and solar energy are each adequate for the next several billion years. That's right; billion not just million or thousand. See the discussion of Energy Problems for the general discussion and the summary of Bernard Cohen's article justifying the billion year estimate.

Q. Isn't it important to conserve energy?

A. Energy needs to be regarded as just another cost, to be used in whatever quantity is cost-effective. It is available in whatever amounts may be needed. Treating its conservation as a special goal has been wasteful of human effort. We are the poorer for it.

Q. Will we run out of minerals?

A. No. There is plenty of every element in major use. It is a question of the economic concepts of reserves and resources. Iron ore and aluminum ore are presently obtained from very rich ores available in a few places in the world. These ores can be shipped long distances by water at small cost. They are oxides rather than silicates which present refining procedures don't handle. The earth's crust is 5 percent iron and 7 percent aluminum, but most of it as silicates. Refining silicates will require more energy. However, the extractive industries only account for four percent of the American GDP, so we can afford more expensive extraction processes when they become necessary.

Indeed once we can extract minerals from random rock, the only way of running out of an element is to eject it from the planet or to let it subduct under a continent. This is because using quantities of elements doesn't destroy them. Therefore, eventually the scrap piles will be ores. This won't happen for a long time, because more concentrated ores will remain available for a long time.

In fact metal ores have become more inexpensive recently as is illustrated by the famous bet between the environmentalist Paul Ehrlich and the economist Julian Simon. In 1980 Simon sold Ehrlich (on credit) ten year futures on five metals of Ehrlich's choosing. The total price was $1,000. In 1990 Ehrlich had to pay Simon $600, because the metals had gone down in price.

Copper is presently being mined in the U.S. at a concentration only ten times its concentration in the earth's crust.

Q. Doesn't the second law of thermodynamics tell us that the lower the concentration of the ore, the more energy it takes to extract it?

A. It does indeed, but the energy required goes up very slowly as the concentration goes down. To separate one mole of a substance from n moles of a substrate requires an energy RT ln n according to the second law. According to this formula, it would pay to extract one atom of uranium from the entire earth. Of course, mineral extraction is more expensive than that, but the second law of thermodynamics isn't the reason. The calculations are given for iron, uranium and the five metals that were involved in the Ehrlich-Simon bet.

Q. What if the population increases?

A. There is certainly a limit to the population the earth can support, and migration into space can only occur very slowly at the present level of technology. The limiting factor may be food, but a feeling that enough is enough may be more important. We will see what happens when 10,000 people try to post to a usenet newsgroup. That won't require any increase in population - only an increase in the availability of computers. Nevertheless, it will give everyone a taste of a more crowded world.

Q. How fast is population increasing?

A. In the U.S., Europe, and Japan, the birth rate is below the level required to sustain the population. The population is increasing because of immigration and from the baby boom that followed WWII. It is the grandchildren of the boomers that are keeping the schools going.

In much of the rest of the world the population is still increasing, but the rate of increase is slowing, especially in the big countries of China, India and Indonesia.

There is still a high rate of growth in Africa, but it also shows signs of slowing.

Q. Is the population problem urgent?

A. Only in a few countries, and it is their problem, because they have sovereignty. People in the advanced countries can only provide technology, but adequate birth control technology has already been provided. For the world as a whole, the population problem may be important, but it is not urgent.

Even for Bangladesh, bad government seems to be more the problem than population per se.

Q. Isn't the world running out of usable fresh water supplies.

A. No, but our civilization may have to spend a lot of money on water projects, just as our ancestors did. For more, see the water FAQ

As might be expected, Population Action International has a different view of the matter from that expressed in this FAQ. We'll get around to criticizing it.

Q. What about the ozone layer and UV-B?

A. On the theory that chlorofluorocarbons put chlorine in the upper atmosphere which destroys ozone, their manufacture has been banned. A 90 percent reduction would have been just as effective and less economically disruptive, but industry seems to be adjusting to the ban.

The theory has widespread acceptance, but there are many scientifically respectable dissenters. Because ozone is regenerated all the time, if chlorofluorocarbons are the problem, the situation will return to normal. There has been much exaggeration of the effects on humans of the increases in UV-B that have actually occurred. Nevertheless, UV-B is harmful to some plants. Experiments with shielding plants from UV-B show that UV-B reduces growth in some plants even at normal levels.

Robert Parson has an FAQ about the causes of the ozone hole in the South Polar Regions. I don't know whether UV-B levels in the U.S. have increased significantly.

Q. Won't global warming do us in unless we drastically reduce our use of energy?

A. No. We will add a discussion of how global warming can be avoided if it should be a serious problem. For now we have a thorough paper by Tom Moore of the Hoover Institution giving reasons why global warming is likely to be good for humanity.
It is also controversial whether global warming is occurring. Should global warming turn out to be a serious problem, there are ways of avoiding it or reversing it.

Q. Given all this uncertainty about the prospects for continuing material progress, isn't it better to be safe than sorry?

A. It is somewhat uncertain, but there is no guarantee of safety in the proposals for limiting human progress. They are likely to cost lives from poverty and make humanity less capable of dealing with dealing with the inevitable emergencies of many kinds. In short, the proposals for safety by restraining progress are more likely to lead to sorrow than continuing progress in general. Of course, particular applications of technology may be harmful, but with all the hype, it is hard to tell which menaces are real and which are imaginary.

Q. This is all very well, but isn't the static American standard of living evidence that some things are getting short and hence more expensive.

A. No. Food, minerals and many manufactured goods continue to decline in price. What has gone up are medical expenses, bureaucratic expenses of all kinds, social security payments and costs of meeting environmental and safety regulations. People voted for these expenses, and the perception that the standard of living hasn't improved may be based on discounting all these increased expenses as not actually contributing to the standard of living.

My opinion is that some of the regulations have been worthwhile, but a great many (probably most) have contributed very little when compared to the costs they have imposed on individuals and businesses.

Here are some references.

I welcome comments, and you can send them by clicking on jmc@cs.stanford.edu

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