6 ms·

Before people freak out about exponential growth, please consider John McCarthy's Slogan. (Yes, that John McCarthy; Lisp isn't the only thing he's done.) He

by mhartl 16y ago

Before people freak out about exponential growth, please consider John McCarthy's Slogan. (Yes, that John McCarthy; Lisp isn't the only thing he's done.) He who refuses to do arithmetic is doomed to talk nonsense. http://www-formal.stanford.edu/jmc/progress/index.html http://www-formal.stanford.edu/jmc/progress/index.html Based on reactions to this video (among other things), I'd add Hartl's Counterpoint: Just because you're willing to do arithmetic doesn't mean you're not talking nonsense. In case you're wondering why you shouldn't freak out, I offer you this: http://en.wikipedia.org/wiki/Logistic_function http://en.wikipedia.org/wiki/Logistic_function

abrahamsen 16y ago
To the point: What seems like exponential growth often turn out to be better described as S-curves.
seabee 16y ago
The video also makes the point that people are ignorant of the exponential function's effect, believing that constant growth is possible, when it clearly is not. The Dr. also mentions that 0% growth is inevitable, so that is covered - but I had no idea it was called the logistic function, thanks.
wazoox 16y ago
Huh. This guy is simply making the very basic point that politicians, economists and bankers selling us "growth" as a solution to unemployment, debt, etc are plainly lying. Growth (population, GDP, energy availability, etc) will stop at some point. An economy that relies entirely on growth to merely function is doomed to fail spectacularly at some point in time.
- dagw 16y ago
  I agree that population growth cannot go on forever (although I consider doubling the current number quite likely). However I see no reason why energy availability can't keep growing for many many centuries to come. We aren't tapping the full potential of nuclear fission, to say nothing about fusion. Things like solar energy in all its variations is also a source we basically aren't using at all. Give us 50-100 years an we'll no doubt come up with some new source of energy we haven't even considered yet.
  - wazoox 16y ago
    > However I see no reason why energy availability can't keep growing for many many centuries to come. We aren't tapping the full potential of nuclear fission, to say nothing about fusion. Nuclear fission is currently on decline. We aren't even building enough power plants to maintain its output, nor are we likely to do so in the next 20 to 30 years. Industrial nuclear fusion is decades away, probably a century. From the 18th century onwards, we went from tapping ever better energy sources (denser, lighter): animal power, coal, oil. There aren't any better energy source than oil available now, or in the foreseeable future. At some point, we'll have to do with /less/.
    - Daniel_Newby 16y ago
      "At some point, we'll have to do with /less/." This part of the long business cycle always produces a lot of arguments for austerity. So far they have always turned out to be spectacularly wrong. "Nuclear fission is currently on decline." Nuclear power, both fission and fusion, is currently in a renaissance and we appear to be laying the groundwork for the next stage of advances: gas- and metal-cooled reactors, superconductors, mechanical compression systems, reliable mode-locked lasers, dielectric wall and wake field particle accelerators, electronics that can do real-time gigahertz feedback, etc. When the next long expansion gets into full swing, I predict that the nuclear logjam will break loose. "There aren't any better energy source than oil available now, or in the foreseeable future." There's a lot of solar power in space. A lot. And literal mountains of metal, richer than the best terrestrial ores and pre-smelted too. At some point technology will tip the profit margin positive on exploiting it.
      - wazoox 16y ago
        > So far they have always turned out to be spectacularly wrong. So far, there weren't 7 billions humans neither. > Nuclear power, both fission and fusion, is currently in a renaissance Absolutely not. This is GE and AREVA PR, but doesn't reflect the truth. We aren't building enough nuclear plants now to compensate for the future closing of the old ones. The numbers aren't even ramping up fast enough. As time goes by, there will be less and less active nuclear plants. Fusion research is blooming, but it didn't make much progress, particularly compared to the huge effort (see ITER). > There's a lot of solar power in space. A lot. And literal mountains of metal, richer than the best terrestrial ores and pre-smelted too. At some point technology will tip the profit margin positive on exploiting it. This is science-fiction. I'm pretty close to say this is complete BS. "Space ore" simply can't happen unless you find the way to harvest the power from some magic ponies yet to discover.
- fgf 16y ago
  nuclear power could deliver far more energy per year than is used yearly now for thousands of years. Innovation makes energy more useful. When the potential for growth these two cause is exhausted there's scifi stuff; solar power from satellites around the sun; fusion; etc.
  - seabee 16y ago
    Right, but it's still finite to some degree, and selling people on growth which we cannot guarantee is possible is just plain irresponsible IMO.
    - anamax 16y ago
      > Right, but it's still finite to some degree, and selling people on growth which we cannot guarantee is possible is just plain irresponsible IMO. Do you plan as if disk drives won't get more capacity? That ram and cpus won't get cheaper? It's only irresponsible if you promise growth that won't happen. It's irresponsible to ignore growth that will or can happen.
- LiveTheDream 16y ago
  Is it still lying if you don't know that you are wrong?
gursikh 16y ago
Dr. Albert A. Bartlett is fully cognizant of that point. He says in part 8 of that video: "Except for the petroleum graphs, the things I tell you are not predictions of the future. I am only reporting facts and the results of some very simple arithmetic." (1:22) He acknowledges the potential fallibility of his estimations. He goes on to say: "Please you check the facts. Please check my arithmetic. if you find errors, please let me know. But if you don't find errors, I hope you take this very very seriously."
rsheridan6 16y ago
In the context of population growth, the logistic function means that something has made it stop. He dealt with this is the second video - he says we'll get zero population growth one way or another, because exponential growth forever is impossible. Around minute 7 of the second video (did you actually watch it?) he points out that many of the checks on population growth are generally considered bad things - war, famine, disease (the alternative being birth control). This is hardly a reason not to freak out.
- mhartl 16y ago
  did you actually watch it? Yes. many of the checks on population growth are generally considered bad things - war, famine, disease The countries with the lowest population growth (e.g., Germany, Italy, Bulgaria, Japan) are among those with the least war, famine, and disease. Something else is going on.
  - presidentender 16y ago
    Do you notice that the countries with the lowest population growth were severely battered in wars during the last century?
    - mhartl 16y ago
      Italian birthrates aren't low because of Il Duce. Once people reach a certain level of wealth, they voluntarily stop having lots of kids.
  - BoppreH 16y ago
    There were many other reasons listed, including low immigration, small families, contraception/abortion, abstinence and pollution. This checks do apply do the countries you cited, but the list is still far from comprehensive. They are far better than war, famine and disease, but still regarded as bad things, which is the point.
    - mhartl 16y ago
fburnaby 16y ago
The reason that the curve levels out for biological populations is that the rates at which members start starving to death or killing each-other increases to cancel out the birth-rate. That does seem to be of some concern.

by mhartl 16y ago

abrahamsen 16y ago

To the point: What seems like exponential growth often turn out to be better described as S-curves.

seabee 16y ago

The video also makes the point that people are ignorant of the exponential function's effect, believing that constant growth is possible, when it clearly is not. The Dr. also mentions that 0% growth is inevitable, so that is covered - but I had no idea it was called the logistic function, thanks.

wazoox 16y ago

Huh. This guy is simply making the very basic point that politicians, economists and bankers selling us "growth" as a solution to unemployment, debt, etc are plainly lying. Growth (population, GDP, energy availability, etc) will stop at some point. An economy that relies entirely on growth to merely function is doomed to fail spectacularly at some point in time.

dagw 16y ago
I agree that population growth cannot go on forever (although I consider doubling the current number quite likely). However I see no reason why energy availability can't keep growing for many many centuries to come. We aren't tapping the full potential of nuclear fission, to say nothing about fusion. Things like solar energy in all its variations is also a source we basically aren't using at all. Give us 50-100 years an we'll no doubt come up with some new source of energy we haven't even considered yet.
- wazoox 16y ago
  > However I see no reason why energy availability can't keep growing for many many centuries to come. We aren't tapping the full potential of nuclear fission, to say nothing about fusion. Nuclear fission is currently on decline. We aren't even building enough power plants to maintain its output, nor are we likely to do so in the next 20 to 30 years. Industrial nuclear fusion is decades away, probably a century. From the 18th century onwards, we went from tapping ever better energy sources (denser, lighter): animal power, coal, oil. There aren't any better energy source than oil available now, or in the foreseeable future. At some point, we'll have to do with /less/.
  - Daniel_Newby 16y ago
    "At some point, we'll have to do with /less/." This part of the long business cycle always produces a lot of arguments for austerity. So far they have always turned out to be spectacularly wrong. "Nuclear fission is currently on decline." Nuclear power, both fission and fusion, is currently in a renaissance and we appear to be laying the groundwork for the next stage of advances: gas- and metal-cooled reactors, superconductors, mechanical compression systems, reliable mode-locked lasers, dielectric wall and wake field particle accelerators, electronics that can do real-time gigahertz feedback, etc. When the next long expansion gets into full swing, I predict that the nuclear logjam will break loose. "There aren't any better energy source than oil available now, or in the foreseeable future." There's a lot of solar power in space. A lot. And literal mountains of metal, richer than the best terrestrial ores and pre-smelted too. At some point technology will tip the profit margin positive on exploiting it.
    - wazoox 16y ago
      > So far they have always turned out to be spectacularly wrong. So far, there weren't 7 billions humans neither. > Nuclear power, both fission and fusion, is currently in a renaissance Absolutely not. This is GE and AREVA PR, but doesn't reflect the truth. We aren't building enough nuclear plants now to compensate for the future closing of the old ones. The numbers aren't even ramping up fast enough. As time goes by, there will be less and less active nuclear plants. Fusion research is blooming, but it didn't make much progress, particularly compared to the huge effort (see ITER). > There's a lot of solar power in space. A lot. And literal mountains of metal, richer than the best terrestrial ores and pre-smelted too. At some point technology will tip the profit margin positive on exploiting it. This is science-fiction. I'm pretty close to say this is complete BS. "Space ore" simply can't happen unless you find the way to harvest the power from some magic ponies yet to discover.
fgf 16y ago
nuclear power could deliver far more energy per year than is used yearly now for thousands of years. Innovation makes energy more useful. When the potential for growth these two cause is exhausted there's scifi stuff; solar power from satellites around the sun; fusion; etc.
- seabee 16y ago
  Right, but it's still finite to some degree, and selling people on growth which we cannot guarantee is possible is just plain irresponsible IMO.
  - anamax 16y ago
    > Right, but it's still finite to some degree, and selling people on growth which we cannot guarantee is possible is just plain irresponsible IMO. Do you plan as if disk drives won't get more capacity? That ram and cpus won't get cheaper? It's only irresponsible if you promise growth that won't happen. It's irresponsible to ignore growth that will or can happen.
LiveTheDream 16y ago
Is it still lying if you don't know that you are wrong?

gursikh 16y ago

Dr. Albert A. Bartlett is fully cognizant of that point. He says in part 8 of that video: "Except for the petroleum graphs, the things I tell you are not predictions of the future. I am only reporting facts and the results of some very simple arithmetic." (1:22) He acknowledges the potential fallibility of his estimations. He goes on to say: "Please you check the facts. Please check my arithmetic. if you find errors, please let me know. But if you don't find errors, I hope you take this very very seriously."

rsheridan6 16y ago

In the context of population growth, the logistic function means that something has made it stop. He dealt with this is the second video - he says we'll get zero population growth one way or another, because exponential growth forever is impossible. Around minute 7 of the second video (did you actually watch it?) he points out that many of the checks on population growth are generally considered bad things - war, famine, disease (the alternative being birth control). This is hardly a reason not to freak out.

mhartl 16y ago
did you actually watch it? Yes. many of the checks on population growth are generally considered bad things - war, famine, disease The countries with the lowest population growth (e.g., Germany, Italy, Bulgaria, Japan) are among those with the least war, famine, and disease. Something else is going on.
- presidentender 16y ago
  Do you notice that the countries with the lowest population growth were severely battered in wars during the last century?
  - mhartl 16y ago
    Italian birthrates aren't low because of Il Duce. Once people reach a certain level of wealth, they voluntarily stop having lots of kids.
- BoppreH 16y ago
  There were many other reasons listed, including low immigration, small families, contraception/abortion, abstinence and pollution. This checks do apply do the countries you cited, but the list is still far from comprehensive. They are far better than war, famine and disease, but still regarded as bad things, which is the point.
  - mhartl 16y ago

fburnaby 16y ago

The reason that the curve levels out for biological populations is that the rates at which members start starving to death or killing each-other increases to cancel out the birth-rate. That does seem to be of some concern.