Progress Will Stop
“If something can’t go on forever, it will stop.”
--Herbert Stein (economist)
Stein’s point in making the above comment was that we don’t need to do anything to ensure that these things that can’t go on forever stop. E.g., the trade deficit can’t grow (relative to GDP) forever; therefore, it will stop, whether we make any effort to stop it or not.
Similarly, population can’t grow forever, since the Earth is finite. The Earth’s population cannot, for example, grow to more than 85 sextillion people, because that is the size at which the entire Earth’s mass would have to have been converted into people. Therefore, it will stop growing (presumably long before that point). Of course, that doesn’t tell us how or when it will stop. People used to worry that it would stop via a sudden disaster killing billions of people. There wasn’t any good reason to believe that, though. We now know what is actually going to happen: as people become wealthier, they naturally start having fewer children. If you look at population growth up to a certain point, it looks like we’re headed for a population of trillions:
But when you extend the graph a little more, it turns out like this:
The qualitative character of that curve shouldn’t surprise us, since we knew almost a priori that population couldn’t grow forever. We should have known that the curve had to level off and possibly decline. (Note: I can’t vouch for this graph being quantitatively accurate.)
The point applies to good trends as well as the bad (or putatively bad). When we think about what the future will be like, we tend to project progress indefinitely. We thus expect our descendants in 2400 A.D. to be living in space colonies; to have genetically engineered bodies immune from disease; to have brain implants that give everyone genius-level intelligence; to have robots to perform every unpleasant task; and of course to all be fabulously wealthy. Some people are more cautious, declining to speculate on what technologies our descendants will have (no doubt they will have some that we cannot now imagine); nevertheless, everyone seems to agree that the future, a few centuries from now, will be vastly better than the present.
I think our projections of the future are likely to be wildly off -- drastically too optimistic -- because we blithely project progress indefinitely into the future. Progress will probably continue for a while yet. But it cannot continue indefinitely, and our descendants will probably be surprised when it stops.
Example 1: Computer Technology
In 1999, Ray Kurzweil, projecting then-recent progress into the future, predicted that by 2019, we would have computers exceeding the computational power of the human brain (https://www.kurzweilai.net/the-coming-merging-of-mind-and-machine). By now, we’re also supposed to have neural implants to improve our memory and reasoning, and by 2029, we’re supposed to have mastered artificial intelligence.
I don’t know whether those things are going to happen, or when. I’m not a computer tech expert. But I know that advances in computer technology cannot go on forever. We will not, for example, ever have an atom-sized computer with the calculating power of the human brain; that is physically impossible.
So computer progress will stop. Some aspects have already stopped. For a few decades of my life, computers kept getting dramatically faster every year. I started with an 8 MHz computer in college; by the time I became a professor, I had a 350 MHz machine. A few years later, it was up to 3 GHz. And there it has remained for the last several years. All the easy ways of speeding up processors, it seems, have now already been done.
Maybe technological advances will go on long enough to give us super-intelligent robots that can solve all our problems and/or threaten our existence. But then again, maybe not.
Example 2: Economic Growth
Economic growth is one of our favorite things to project into the future. In 400 years, surely, everyone will be fabulously rich. Average people will live better than today’s millionaires. In Star Trek, it is said that human society has no use for money, because material scarcity has ended.
I’m not sure all that is going to happen, though. The rate of economic growth is on a long-term declining trend:
Why? My guess: we’ve picked the low-hanging fruit. That is, the easiest ways of increasing productivity have already been implemented by now. As our economy gets more efficient, it gets harder and harder to find ways of significantly improving it more. So the growth rate has to decline. Eventually, it will reach zero.
Btw, I’m sure we can improve things a good deal more yet, but I’m not sure we will, since further large improvements might require unpopular political changes (drastically reducing regulation, taxation, etc.). In any case, growth won’t continue forever. I don’t know when it will stop, but I wouldn’t be shocked if it stopped within a century.
Example 3: Knowledge
I suppose we’re expecting to have solved the mysteries of the universe within the next few hundred years, or at least the next thousand. That seems reasonable given the amount of progress over the last thousand years.
And maybe we will. But that isn’t obvious. As human knowledge advances, our existing body of knowledge becomes more complicated and difficult to grasp. It requires longer training and higher intelligence to master it, and it requires more work by more people to make further advances. Eventually, humanity will reach the limits of its intellectual capacity. We can then keep piling on more researchers doing correlational studies of different combinations of variables, but that has diminishing returns and won’t advance fundamental understanding.
We’re already at a stage where you have to be in about the top 0.01% of the population in intelligence, and you have to study for several years, just to understand the cutting-edge theories in physics. Almost no one is up to speed on the current theories in more than one field of human intellectual inquiry. What if truly understanding our world requires integrating knowledge from multiple different fields of study?
A Metaphor
Imagine that you’re an angelic intelligence just created by God. You’ve never seen a human before. You get to observe one human being, who has just been born. As you watch this person grow from a baby to an adolescent, you think, “In 100 years, he’ll be the size of a house and have the strength to lift several tons. He’ll also have mastered every major branch of mathematics and science.” You would be disappointed as his growth stopped shortly thereafter. You’d be even more disappointed as this human started to grow old, his body and mind deteriorated, and eventually he died. You couldn’t be blamed for not anticipating all this, though, because you had never seen a complete human life-cycle before.
That’s how things work in the real world. Real curves don’t go off to infinity like in mathematics. Real curves level off and then decline.
Our civilization is like that human. This is the only technological civilization that we’ve observed, so we don’t know what to expect. We don’t know if it’s in its childhood, adolescence, or young adulthood. And we’re going to be disappointed when it stops growing, then eventually declines.