Malthus and the Vicious Circle Principle

It is ironic that both those, like myself, who call themselves "Malthusians" and those who declare their antipathy to Malthusianism share a common trait. We don't seem to know or understand what Malthus actually said or meant. Here, Craig Dilworth sets the record straight by showing us where Malthus was right and where he was wrong, and in so doing, offers us an insight into the role that technology plays in population overshoot. I expect that Craig's recently published book, Too Smart For Our Own Good will take its place along side William Catton's "Overshoot" as a landmark of ecological understanding. I am looking forward to reading it. This submission should whet our appetites. -- Tim Murray

The Principle of population

Thomas Malthus (1766–1834) is best known for his principle of population, published in 1798 in the first edition of his Essay on the Principle of Population. There he characterises it as “The perpetual tendency in the race of man to increase beyond the means of subsistence,” which he considers to be “one of the general laws of animated nature which we have no reason to expect will change.” (p. 199).

In discussions regarding the principle it has only been taken in its application to humans. But, as suggested by Malthus above, as well as more explicitly in his Summary View of the Principle of Population (1830, p. 225), it is clear that it should apply to any animal or plant species. Thus the principle of population is a biological principle, moreover, one that is necessary to Darwin’s principle of evolution. If populations of organisms didn’t tend to increase in size, and compete over a common resource in so doing, there would be no survival of the fittest or natural selection resulting in species evolution.

Note that the principle is to apply at all times, and not only at some, perhaps future, time. (See p. 101 of my book, Too Smart for Our Own Good.) Malthus says:

[T]he pressure arising from the difficulty of procuring subsistence is not to be considered as a remote one, which will be felt only when the earth refuses to produce any more, but as one which not only actually exists at present over the greatest part of the globe, but, with few exceptions, has been almost constantly acting upon all the countries of which we have any account. (1830, p. 247).

The misunderstanding of the principle in this regard has recurred ever since the time of Mal-thus, with people more often than not saying that Malthus is making some sort of prediction regarding the future. According to Malthus, and as applied to humans in particular, the popu-lation principle suggests rather that since we can only increase agricultural area arithmetically, while the population has a tendency to grow geometrically, there has always been and will continue to be a “difficulty of subsistence … This difficulty must fall somewhere and must necessarily be severely felt by a large portion of mankind.” (1798, p. 81).

Here however we should say that Malthus is mistaken in drawing this conclusion. Keeping in mind that the principle of population is to apply not only to humans but to all forms of life, we point out that in the case of animals living in the wild there is no general difficulty of subsis-tence. When we look more particularly at K-selected species – i.e. species whose members characteristically live a number of years – we find that their populations are generally well fed, counter-instances only occurring during unusual periods of drought, etc. Similarly, there is no difficulty of subsistence among modern hunter-gatherers. In other words, the populations of non-human species and modern hunter-gatherers are kept below a level that would result in a persistent problem of subsistence.

This is effected through the workings of various sorts of population check, both internal, such as contraception, infanticide or monogamy (in the case of humans), and external, such as famine, disease or predation. Some of those affected by such population checks – such as in-fants who are killed, or individuals who die of hunger – certainly experience a “difficulty of subsistence.” But their doing so does not constitute a persistent state of affairs, such as is in-timated by Malthus, according to whom a large portion of the population is always to be mal-nourished and/or overworked. Those members of the population that are not eliminated by internal or external checks generally thrive. What Malthus characterises as “the problem of subsistence” does not exist for non-human species, and has existed for humans only in the last 5000 years.

Though Malthus was aware of the existence of internal population checks (1830, p. 249), he never realised how powerful they can be and have been with regard to the human species. Nor did he realise that human society need not be hierarchically ordered such that those on the bottom suffer from overwork or malnutrition, both of which insights he might have obtained from a study of other animal species or modern hunter-gatherers, the latter of which he be-lieved to suffer from population pressure (1798, p. 77). Nor, it may be mentioned, did Malthus give any consideration to the relation between population size and ecological equilibrium, or technological innovation and temporary carrying capacity, or the fact that the human population has constantly grown, while the populations of other animals increase and decrease in cycles.

Thus while we should accept the principle of population, that all species, including humans, tend to increase beyond their means of subsistence, we point out that they are prevented from doing so by various kinds of population check, such that it is not the case under normal cir-cumstances that a large part of any one population severely feels the difficulty of subsistence. This is certainly not the case for wild animals, nor for early humans. But what can be granted Malthus is that, at least since the time of the first civilisations 5000 years ago, it has as a mat-ter of fact been the case for humans. But the reason for this has yet to be given.

The vicious circle principle

In Too Smart for Our Own Good I offer an account of the whole of the development of Homo sapiens; and in that account the suffering of the weak after the agrarian revolution some 5000 years ago has a natural place. My explanation is based on what I call the vicious circle principle, which is as follows:

Humankind’s development consists in an accelerating movement from situations of scarcity or need, to technological innovation, to increased resource availability, to increased consumption, to popul¬ation growth, to resource depletion, to scarcity once again, and so on.

The vicious circle principle (VCP) is both easy to understand and in keeping not only with modern science but also with common sense. Briefly put, it says that in the case of humans the experience of need, resulting e.g. from changed environmental conditions, sometimes leads to technological innovation, which becomes widely employed, allowing more to be taken from the environment, thereby promoting population growth, which leads back to a situation of need. Note that the turning of the vicious circle normally leads to a constantly increasing human population.

We see here that the VCP is unlike the population principle in that it is intended to apply only to humans. Also, where the population principle relates only to population size and subsis-tence, the VCP concerns a greater number of variables, including technological innovation, resource availability and population growth. And on top of this the VCP has a dynamic ele-ment, saying that the relation among these parameters is one of an accelerating cycle. The rate at which new technology is implemented and the human population grows is constantly in-creasing.

On the VCP the poor living conditions of the weak are a result of the stratification that devel-ops as the population grows. In primitive groups – bands or tribes – the leaders’ quality of life was the same as that of the other members of the tribe, and the workload was never great. But as the vicious circle turns the workload increases, and what were once leaders of perhaps a few hundred people become leaders of thousands. Thus, by the time of the agrarian revolution some 5000 years ago, we arrived at situation where two classes had developed: the tiny class of the rulers, and the massive class of the common people who toiled for the rulers and fought in their armies. It was only when this stage in the development of humankind was reached that Malthus’ description becomes correct, and we have a situation where the vast majority of the people labour for the leader, such that there is a general difficulty of subsistence among the populace, while the leaders lead lives of luxury.

Craig Dilworth

References
Dilworth, C. (2010) Too Smart for Our Own Good, The Ecological Predicament of Human-kind, Cambridge: Cambridge University Press.
Malthus, T. R. An Essay on the Principle of Population and A Summary View of the Principle of Population, Harmondsworth: Penguin Books, 1970.
––––– (1798) An Essay on the Principle of Population, pp. 59–217 of Malthus.
––––– (1830) A Summary View of the Principle of Population, pp. 219–272 of Malthus.