Monday, January 12, 2015

#12 / The Exponential Function

I have written several blog posts touching on the "exponential function," though I haven't used exactly that wording to describe what I was talking about. For instance, you could review:

Recently, a Facebook Friend alerted me to an excellent video by Al Bartlett, an Emeritus Professor of Physics at the University of Colorado at Boulder. Bartlett makes exceedingly clear exactly how the exponential function works, and what it means to us. I commend his presentation to you.

Bartlett's presentation comes in two flavors: (1) a single lecture, titled "Arithmetic, Population and Energy," that is about an hour and fifteen minutes long, and (2) the same lecture broken down into ten-minute segments.

The bottom line? Vigorous, healthy growth is going to kill us all!

Let's try standing still for a while. As Regina Spektor says, that's "hard."

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  1. You seem not to have been paying attention to the lecture, Gary. Vigorous, healthy growth is impossible. Us all being killed contradicts vigorous, healthy growth.

    Your prescription of "standing still" is redundant because the population growth is already approaching zero [1] for reasons other than your whining. World population is projected to peak below 9bn by 2050 [2]. We wave technology to thank for this trend. Birth control, first and foremost. Next comes large scale agriculture, which freed people from the need to pump out children as cheep farm labor. And finally, we have medicine, which has allowed people to enjoy long, healthy reproductive years, so that having children is less of a frenzied biological obligation, and more of an expression of love and commitment.

    You might want to take a moment to reflect on how your anti-technology world-view forces you to oppose the very saving graces which will solve Al Bartlett's problem of growth.


  2. Growth is not solely a result of birth rate.

    The impact of humans on the natural world is a function of number of humans multiplied by their level of consumption. In order to reduce our destruction of the natural world, we must either lower our population or decrease our per capita consumption... or, better yet, both.

    Even though birth rates in some countries are declining, increase in consumption levels rapidly overtakes fewer individuals, resulting in a net increase in consumption of resources.

    This is not an "anti-technology" world view. Technology continues, even in a world of fewer people and less consumption. It's a matter of appropriate technology employed wisely, in the overall perspective of humans as one species among many in a world of finite resources.

    Modern decreases in birth rate are not a result of the technology of birth control, which has been available for centuries. It is a result of social changes that give women more control over their lives and reduce the necessity of large families.

    Industrial agriculture and medicine increase the level of consumption at the same time that they encourage population growth, a double whammy to the natural world.

    Continuous growth will not result in us all being killed. We will all die, many of us of natural causes. The important thing is that the level of replacement declines, such that overall population levels worldwide are reduced to a point where consumption of resources does not exceed the rate at which they are naturally replenished, and production of wastes does not exceed the rate at which they are naturally assimilated.

  3. Gary absolutely does hold an anti-technology world view. This post is an example of how that world view forces him to oppose the very saving graces which will solve Al Bartlett's problem of growth. Economic growth and resource consumption aren't solely a result of the population growth rate, but Al Bartlett was talking specifically about population growth.

    What gives women more control over their lives than the pill? It's introduction in the 1960s caused the steepest decline in population growth the US has seen since WW2 [1]. Technological infrastructure predicts gender egalitarianism [2], as well as education, etc.

    Again, Michael, you demand lowering of and/or decrease in per capita consumption without giving any suggestion *how* this can be accomplished! This is the problem you and Gary seem to have. You're good at whining, but not very good at coming up with solutions. Because you guys are ideologues.

    Al Bartlett presents a list of dials. The question is, which dials do we turn? We can turn up food production to meet the world population at its predicted peak at 9 billion in 2050. That will require more than standing still. It will require hard work and letting go of dreams that all those billions of people will somehow be removed from the moral calculus.



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