That is not exactly what I am saying. In one of my previous posts I stated that it is also the fraction of people with the required education to do useful research in the population that matters.
However, when the population stabilizes and stops growing, and most people around the world attain the educational standards common in developed world today, there won't be any room for further expansion.
But the thing is, we are very very far from a point where most people in the world attain the educational standards of the developed world. So there's plenty room to grow even after the population stabilizes.
Not only that, there is no reason why the proportion of researchers in the developed world should remain constant. I think (and hope) that future economic pressures will greatly reduce the demand for lawyers, accountants and etc, and increase demand for researchers. In short, I don't think that stagnation of the number of researchers need be a problem.
I believe the contrary is true. Today's inventions are much more complicated and require much more initial investment (both in terms of money and education). 100 years ago, you could discover a new physical phenomenon in the lab you had in your basement. Today, you need something like the Large Hadron Collider, an enormous and very expensive instrument that took decades to set up.
I also don't believe that you can simply translate the number of researchers into the number of inventions. As I said, today's inventions take much more effort ("research points", in gaming terminology) to complete, so usually research is a collective effort, with large international teams working on one problem. Hence, to make a new invention today requires more people researching it. So far, we've been able to supply more researchers and more money to keep up the rate of discovery, but again, this won't continue forever.
But empirically we have seen that returns on research are not diminishing. If we take what you said as true, from the moment we started doing scientific research in the 17th Century, all the way to the present, returns should be diminishing, as innovations became more and more complex. But they have not!
The effects of "standing on the shoulders of giants" seem to compensate the "exhaustion of easy paths".
It's undeniable that a researcher now is much more productive than in the past- this is an objective fact that can be measured by the number of patents per capita. How could he not be, with absurd processing power at his disposal, and all previous research readily available?
Also, research is a general term which encompasses many different activities. I am sure thousands of research workers are trying to develop a luminescent lipstick or something equally extravagant, although with their qualification they could just as well be working on a new chemotherapy for cancer or something equally beneficial. Worse, basic research is getting both more difficult and less attractive for the main investors. It's possible that in the future we'll focus more on developing applications of existing knowledge without really trying to go for breakthroughs that would open entirely new paths of research. (That is basically what the Middle Ages were about - people worked with existing knowledge, and pretty much perfected its applications - the notion that the Middle Ages were times when no progress was being made is entirely false, it was just a lot slower than it is today.)
You're underestimating the potential of breakthroughs while researching shiny lipstick! Throughout the history of science, major breakthroughs were achieved while researching something unrelated. You may start researching some fluorescent substance for lipsticks and end up discovering a cheap light-emitting substance with all sorts of practical applications.
And I absolutely see no risk of we moving towards mostly perfecting what we already have. Research is fields like physics is so theoretical and advanced these days that my head hurts just reading a paper, and I am an engineer.
Actually, we're getting close to the limit of what we can squeeze from the environment. We're already using more than can sustainably be extracted.
I don't think that can be demonstrated.
But in any case, even if resources on Earth were unlimited, humans can't really consume infinite amounts of products and services. Already people in most developed countries are living pretty comfortable lives. Even if they could consume more, would they? In fact, progress in science and technology can make people consume less. For example, say a Matrix-like virtual reality networks are created. How would this affect the airlines, the tourism industry, and other "luxury" services? Why would I pay a lot of money to spend two week in Maldives, if I could just do the travelling from my home and the experience was almost the same? Actual physical travel would sharply decline then, so the overall impact on the economy, employment, etc. would be negative.
A Matrix-like realistic virtual environment would be a major undertaking requiring a huge investment and maintenance, both in hardware and software. A virtual trip to the Maldives might one day be cheaper than a real one, but it won't be free. A new economy would develop on the virtual world, and indeed total output would increase, not decrease.
As for the fact that the developed world has already reached comfortable standards of living and needs go no further, you have to keep in mind that comfort is a relative concept. A middle class American family of the 50's also had a comfortable life. But the amount of resources needed to sustain their lifestyle - the amount of dollars needed per month - was vastly inferior to that of an American middle class family of the present. A modern family will travel much more by plane, will own multiple flat screen TVs with home theaters, laptops, videogames, iPads, kitchen appliances, etc. They will go the gym, the kids will take jiu-jitsu and french and piano classes, and so on and so forth. Likewise, in future all sorts of "new demands" will show up. Nobody needed a fast internet connection or an iPad 20 years ago, and life was already pretty good. But that doesn't mean people won't want them now.
Now, in a world with limited resources (a much likelier scenario), your consumption will be restricted not only by the money you earn, but also by regulation designed to prevent a resource overdraw.
Really, we need to start getting used to the idea of a limited world with limited resources and try to make sure we can make the most of it. Pinning our hopes to the illusion of ever increasing growth and ever faster technological progress is folly.
Also, the sooner we expand beyond Earth, the better - it's the only way to conciliate unlimited growth of humanity with the limitations of our environment.
If you think about it, the one and only resource we truly need an en ever expanding supply of is energy. And as I said, there are gigantic untapped opportunities out there that can sustain our growth virtually forever.
luiz: keep in mind that Winner is saying that technological advancement will continue, even with a stabilizing population. It's just that certain exponential components will no longer be there (i.e., increasing educated base). I think it's clear that if the number of educated workers is increasing, that will contribute to total trend of exponential increase!
Sure, but as I said, there are two things to consider:
-We're still very very far from a point where the whole world has developed levels of education, and thus there is great growth potential.
-There is no reason why the composition of the educated workforce should remain constant forever. In the present, a lot of people that go to college study Law, or political science, etc. Depending on the pressures of the future, more people could turn into research. In fact, if we look at rapidly developing nations like China and South Korea, we note that a very high proportion of their educated workforce is on technical careers, when compared to the West. To keep it's competitive edge, the West will have to do the same.
