4 ms·

I agree that these aren't Malthusian, and some aren't even true. The ones that are true seem to exemplify incentives and constraints. When you have an incentive

by SiVal 14y ago

I agree that these aren't Malthusian, and some aren't even true. The ones that are true seem to exemplify incentives and constraints. When you have an incentive to do more, you do more until either the incentive (marginal_benefit - marginal_cost) or your ability to do a little more fades to zero. When the incentives or constraints change, the behavior adapts accordingly. A Malthusian collapse is a special case that is not relevant to most situations of incentives and constraints.

CWuestefeld 14y ago
But the reason that Malthus' doom-mongering hasn't come to pass is because he failed to consider that there was sufficient incentive for people to find alternatives, such that they could skirt the constraints. Malthus said that the carrying capacity of Earth is limited to X because of finite arable land (and so on). But then humans came up with irrigation, and crop rotation, and terracing, and selective breeding, and fertilizers and insecticides, and powered machinery, etc., all of which allowed the Earth to provide for ever-increasing numbers of people. Malthus saw humanity as limited to subsistence dirt farming, but the people saw the ability to prosper, have large families, etc., as sufficient incentive to invent alternatives. The incentives didn't change, and the constraints only changed so far as did the body of human knowledge.
- slowpoke 14y ago
  It is true, though, that there is a limit to how much people this planet can reasonably sustain, and I'd say we're billions over that mark - the only reason the system still works (barely) is because a large part of the world's population lives in poverty and hunger. Optimization will only get you so far. We simply can't optimize away the fact that there is limited space on this planet and that we're pretty much out of it already. We can't sustain 7 billion people, tendency growing. Not at a humane average living standard.
  - kbolino 14y ago
    I don't think you deserve the downvotes; your point may be valid, even if pessimistic. Just because we've managed to overcome what seemed to be infeasible hurdles doesn't mean we will continue to do so. Of course, just because the new hurdles seem even less feasible doesn't mean we won't overcome them, either. The point being that you'll never know you're at the cusp until you're well into the valley on the other side. Malthus was wrong about the long-run behavior of populations, but I think it's worthwhile to note that we can feed yesterday's population today. World hunger could have been a solved problem with all the advances that were made. But who has the right to tell you not to breed?
    - CWuestefeld 14y ago
      Well, the argument needed to be made because there are so many who subscribe to it. But the important point that this misses is that the availability of any given resource isn't what's critical, since all throughout history it's been shown that human ingenuity has been able to find alternatives. The critical factor is that human ingenuity. And because that human factor -- the availability of someone who can figure out that alternative, and who has the incentive to do so -- is growing with the growth of the population, are horizons are only broadening! Contrary to Malthus, an increasing population is, in the long run, better for mankind's prospects.
      - _delirium 14y ago
        I'm not at all sure the last part is true. It's difficult to do experiments in history, of course, but there are historical examples of quite fast-advancing societies with smallish, stable populations, and of not-making-progress societies with large and growing populations. Enough that I doubt any general causal relationship between population growth and technological advances or quality of life.
      - baq 14y ago
        to paraphrase a classic: "on this planet, we obey the laws of thermodynamics." can't be bothered to explain in detail, leaving a link to a most interesting blog instead: http://physics.ucsd.edu/do-the-math/2012/02/the-way-is-shut/ http://physics.ucsd.edu/do-the-math/2012/02/the-way-is-shut/. i assume increasing population => increasing energy demand.
  - rimantas 14y ago
    And the biggest growth is in places where it is least sustainable. However, as far as I understand hunger is not a problem of the quantity of the food, it is a problem of distribution. I do hold somehow cynical view, that the bigger percentage of humanitarian aid should be in form of condoms, not food.
- gwern 14y ago
  > But the reason that Malthus' doom-mongering hasn't come to pass is because he failed to consider that there was sufficient incentive for people to find alternatives, such that they could skirt the constraints. No, his doom-mongering was wrong because the alternative to collapse he laid out as improbable - 'moral restraint' - turned out to actually happen, leading to the very strange phenomenon known as the 'demographic transition'. Which we still don't understand why it happened, how long it will last, or where it will break down and how, so I don't blame Malthus. I do blame Internet commenters facilely writing off Malthus as falsified by technology. Go actually read his essays! No, some geometric improvements in irrigation and fertilizers do not disprove him. Agriculture is not expanding exponentially: what happened was the population stopped growing as fast as it could. That is all.
  - CWuestefeld 14y ago
    the population stopped growing as fast as it could. That is all. No. Population growth has slowed, but not stopped. Of the 7 Billion people alive today, how many of them are not better off than virtually anyone of Malthus' day 200 years ago? How many people have no access to antibiotics, running water, and a wealth of conveniences that they take for granted? Yes, there are many people that don't have these advantages. But today, much of the world is better off than virtually anyone from 2 centuries past. So that's not all, there must be something else. The Simon/Ehrlich wager did not involve population statistics at all. It involved changes in the prices of commodities. In other words, Ehrlich (the Malthus disciple) lost the bet because in real life, people find substitutes for resources for which prices are increasing. Thus quantity demanded decreases, and eventually price decreases. Our ancestors used to hunt whales into oblivion to get (amongst other things) blubber to fuel lamps. But as the whale population decreased, so did the supply of blubber, and thus prices rose. That led to people finding alternative means of lighting, and the end is that we don't hunt whales hardly at all anymore. Thus, the fact that greater tension between resource availability and quantity demanded lead to increased prices. That causes somebody to say to himself "if people are willing to pay so much for resource X, they'd be willing to pay just a little less to me for an alternative". He figures out how, people switch, and the market for resource X declines.

by SiVal 14y ago

CWuestefeld 14y ago

But the reason that Malthus' doom-mongering hasn't come to pass is because he failed to consider that there was sufficient incentive for people to find alternatives, such that they could skirt the constraints. Malthus said that the carrying capacity of Earth is limited to X because of finite arable land (and so on). But then humans came up with irrigation, and crop rotation, and terracing, and selective breeding, and fertilizers and insecticides, and powered machinery, etc., all of which allowed the Earth to provide for ever-increasing numbers of people. Malthus saw humanity as limited to subsistence dirt farming, but the people saw the ability to prosper, have large families, etc., as sufficient incentive to invent alternatives. The incentives didn't change, and the constraints only changed so far as did the body of human knowledge.

slowpoke 14y ago
It is true, though, that there is a limit to how much people this planet can reasonably sustain, and I'd say we're billions over that mark - the only reason the system still works (barely) is because a large part of the world's population lives in poverty and hunger. Optimization will only get you so far. We simply can't optimize away the fact that there is limited space on this planet and that we're pretty much out of it already. We can't sustain 7 billion people, tendency growing. Not at a humane average living standard.
- kbolino 14y ago
  I don't think you deserve the downvotes; your point may be valid, even if pessimistic. Just because we've managed to overcome what seemed to be infeasible hurdles doesn't mean we will continue to do so. Of course, just because the new hurdles seem even less feasible doesn't mean we won't overcome them, either. The point being that you'll never know you're at the cusp until you're well into the valley on the other side. Malthus was wrong about the long-run behavior of populations, but I think it's worthwhile to note that we can feed yesterday's population today. World hunger could have been a solved problem with all the advances that were made. But who has the right to tell you not to breed?
  - CWuestefeld 14y ago
    Well, the argument needed to be made because there are so many who subscribe to it. But the important point that this misses is that the availability of any given resource isn't what's critical, since all throughout history it's been shown that human ingenuity has been able to find alternatives. The critical factor is that human ingenuity. And because that human factor -- the availability of someone who can figure out that alternative, and who has the incentive to do so -- is growing with the growth of the population, are horizons are only broadening! Contrary to Malthus, an increasing population is, in the long run, better for mankind's prospects.
    - _delirium 14y ago
      I'm not at all sure the last part is true. It's difficult to do experiments in history, of course, but there are historical examples of quite fast-advancing societies with smallish, stable populations, and of not-making-progress societies with large and growing populations. Enough that I doubt any general causal relationship between population growth and technological advances or quality of life.
    - baq 14y ago
      to paraphrase a classic: "on this planet, we obey the laws of thermodynamics." can't be bothered to explain in detail, leaving a link to a most interesting blog instead: http://physics.ucsd.edu/do-the-math/2012/02/the-way-is-shut/ http://physics.ucsd.edu/do-the-math/2012/02/the-way-is-shut/. i assume increasing population => increasing energy demand.
- rimantas 14y ago
  And the biggest growth is in places where it is least sustainable. However, as far as I understand hunger is not a problem of the quantity of the food, it is a problem of distribution. I do hold somehow cynical view, that the bigger percentage of humanitarian aid should be in form of condoms, not food.
gwern 14y ago
> But the reason that Malthus' doom-mongering hasn't come to pass is because he failed to consider that there was sufficient incentive for people to find alternatives, such that they could skirt the constraints. No, his doom-mongering was wrong because the alternative to collapse he laid out as improbable - 'moral restraint' - turned out to actually happen, leading to the very strange phenomenon known as the 'demographic transition'. Which we still don't understand why it happened, how long it will last, or where it will break down and how, so I don't blame Malthus. I do blame Internet commenters facilely writing off Malthus as falsified by technology. Go actually read his essays! No, some geometric improvements in irrigation and fertilizers do not disprove him. Agriculture is not expanding exponentially: what happened was the population stopped growing as fast as it could. That is all.
- CWuestefeld 14y ago
  the population stopped growing as fast as it could. That is all. No. Population growth has slowed, but not stopped. Of the 7 Billion people alive today, how many of them are not better off than virtually anyone of Malthus' day 200 years ago? How many people have no access to antibiotics, running water, and a wealth of conveniences that they take for granted? Yes, there are many people that don't have these advantages. But today, much of the world is better off than virtually anyone from 2 centuries past. So that's not all, there must be something else. The Simon/Ehrlich wager did not involve population statistics at all. It involved changes in the prices of commodities. In other words, Ehrlich (the Malthus disciple) lost the bet because in real life, people find substitutes for resources for which prices are increasing. Thus quantity demanded decreases, and eventually price decreases. Our ancestors used to hunt whales into oblivion to get (amongst other things) blubber to fuel lamps. But as the whale population decreased, so did the supply of blubber, and thus prices rose. That led to people finding alternative means of lighting, and the end is that we don't hunt whales hardly at all anymore. Thus, the fact that greater tension between resource availability and quantity demanded lead to increased prices. That causes somebody to say to himself "if people are willing to pay so much for resource X, they'd be willing to pay just a little less to me for an alternative". He figures out how, people switch, and the market for resource X declines.