I remember reading the book when I was a junior in engineering. If I recall correctly (it’s been a LONG time), but book actually was careful to not spell out exact dates, but general trends. The horizon for collapse could have been as short as 50 years but as long as several hundred. The thesis was ultimately rejected because it didn’t take sufficient account of changing technology to control pollution, improve crop yields, etc.
But, it is probably correct over the long run, say several centuries or maybe even millennia. The earth sustains 7 Billion people today. Can it sustain 15 Billion? 25 Billion? 100 Billion? 200 Billion? 500 Billion?
At some point, you do run into the “carrying capacity” of the planet — arable land is finite, the earth’s crust is only so thick and endowed with only so many minerals, and the atmosphere only a few miles deep.
Should we spend any time, energy and money worrying about such things today?
The developed countries now have below replacement levels of fertility. If their populations are growing, it is because of immigration (e.g. the U.S.). Fertility rates are declining in the developing world as well as these countries become more prosperous.
Lesson: mass prosperity is the answer to Malthus. Above a certain threshold, affluent people delay marriage and reduce family size. (Many more years in school; kids are more expensive to raise, etc.)
So, long term? Energy is not a limiting factor. Sooner or later, we will go nuclear, though we may have to exile the enviros to a desert island first. Water will be a problem, but in the long run we will desalinate. Arable land is limited; there is still growth potential -- considerable growth potential, with GMOs -- but diets may have to change. There may be any number of bottlenecks along the way, but there are also workarounds on most technologies. If population stabilizes, we will be ok.
“At some point, you do run into the “carrying capacity” of the planet — arable land is finite, the earth’s crust is only so thick and endowed with only so many minerals, and the atmosphere only a few miles deep.
Should we spend any time, energy and money worrying about such things today?”
Yes, the only way to survive is to colonize other planets or construct our own. We pretty much have the building for all the technology needed so there is no time like the present.
Every day, a single catastrophic event on this planet could spark a collapse and prevent us from doing so forever.
building > building blocks