Escaping Malthus

How have we escaped the Malthusian trap, and is our escape only temporary? Malthus argued that human population was naturally at the limit of what resources could support. To put it another way, the very poor were always on the edge of starvation. Any increase in resources would only bring temporary respite: the population would increase, and once again the poor would be starving.

While a good part of the world is still in a Malthusian regime, it is clear that the western countries are not. Why not? Malthus’s argument is fairly general and fairly strong.

The escape would seem to be due to technology. Not just technology, but the ability to harness energy not directly produced by humans and animals. It’s sometimes difficult to grasp, but just 250 years ago there was very little non-human, non-animal energy available. People used water-wheels and windmills to grind wheat, and they used wind power to move boats, and they used gunpowder to fire weapons. But food was grown and distributed entirely by human and animal labor.

The invention and commercialization of the steam engine, and the subsequent industrial revolution, provided a new source of power. According to Malthus’s argument, the population would have been expected to grow enough to consume all the newly available resources. But that didn’t happen. It didn’t happen because the new machinery generated so much power that the human population could not grow fast enough to use it up. For the first time in human history, resources grew faster than population.

It’s worth considering where those resources came from. Initially they came from burning wood. But pretty soon, people burned coal. Later came natural gas and oil. That is, the industrial revolution was based on consuming solar energy which was collected by plants and then stored in the earth over millions of years. The process of creating new coal and oil is ongoing, but the existing resources were consumed at a completely unreplenishable rate. The key to escaping Malthus’s argument turns out to be the consumption of resources which were previously unavailable, and to consume them at an extraordinary rate.

We’re still doing that today, of course. This raises the spectre that Malthusian life has only been evaded temporarily. When we run out of oil and coal, our resource usage may crash, which will be followed by a population crash, and human life will return to a Malthusian regime.

Can we escape that? One interesting fact we’ve discovered is that when people have sufficient resources, they have fewer children. This seems to be true in a number of different cultures. This is something which Malthus did not anticipate, as it implies that given sufficient resources, there is a natural limit to human population.

Do we have sufficient resources? Today, we clearly do not. The wealthy countries are consuming stored solar energy much faster than it is being created, and the poorest countries are essentially Malthusian regimes. Can we find new sources of energy? There are many possibilities. The only ones which could possibly work in the long term are the ones which are unbounded at human scales: geothermal energy, solar energy, and fusion power. Wind and tidal power use the rotational energy of the earth, which effectively can not be diminished, but they don’t seem to provide enough energy for us, so they can’t be a complete solution. Ethanol is a form of solar energy. None of the possibilities are sufficient today; the question is whether we can make them sufficient before our current energy regime expires.

Our current society is similar to a gambler who borrows money to start playing roulette and keeps putting his winnings back on the table. It is possible for the gambler to finally win enough money to come out ahead. It is also possible that the gambler will wind up losing everything.