On Malthusian Theory of Population

This post revisits ‘An Essay on the Principle of Population’ written by Thomas Malthus in 1798. In my last post I briefly touched upon his population theory. Unfortunately, mainstream economics textbooks mention Malthus only for his ‘bad’ population theory. His other significant contributions like Differential Theory of Rent, his theory of money, his questions about the validity of Say’s law, etc are conveniently suppressed.

First, I would like to discuss why his theory is ‘good’ and then I would like to show how Malthus is viewed, interpreted and treated by various economists and students of economics.

Economics as viewed earlier and as viewed now (by a few) was a discipline which tried to understand the society (now known an economy) and also to come up with solutions for the problems that persist. His Essay was the first serious economic study of the welfare of the lower classes” during his times. He was also a clergyman who wanted to make the society perfect.

His two postulates were that “food is necessary to man” and that “the passion between the sexes is necessary and will remain nearly in its present state”. [Malthus 1798] Now we know that the first is a true premise and the second one is believed to be a law of nature. So, there are no issues with both his postulates. He also refers to these postulates as ‘laws of nature’.

Ceteris paribus, population growth will outstrip food growth. He also gives additional insights as to how population growth will necessarily be checked. His thought experiment based on the ‘true’ premises is therefore valid. At this juncture, one needs to understand the underlying assumption of diminishing returns to agriculture. Once this is understood, there is no reason to call his theory ‘bad’.

How can such a theory be useful to the society? It brings to the fore the need for improvements in agriculture through technological advances, so that food production can be increased. (Assuming increased food production implies lesser hunger, but Amartya Sen proved otherwise. But it is necessary to have sufficient ‘food’ to feed society) Family planning is undertaken so that no child goes hungry apart from other reasons. Such checks are welcomed by all. Also, they indirectly draw from Malthus- the need for all people to consume food. However, checks like the Chinese one child policy create social problems on a massive scale.

It is amazing that even when his theory is viewed in isolation (from his other works), it still holds good! With progress in education (school children get introduced to a lot of theories and facts at an early age) theories like Malthus’ seem obvious and hence pointless. This also reflects the way theories are taught in schools and colleges. Very often, the context of the theory is left out. Corn Laws, the then predominant Ricardian theories, etc are very often not mentioned or discussed.

Now, I shall put forth two different views on Malthus, the economist.

1)

In this famous work, Malthus posited his hypothesis that (unchecked) population growth always exceeds the growth of means of subsistence. Actual (checked) population growth is kept in line with food supply growth by “positive checks” (starvation, disease and the like, elevating the death rate) and “preventive checks” (i.e. postponement of marriage, etc. that keep down the birth rate), both of which are characterized by “misery and vice”. [Source] (Note the mention of (unchecked))

2)

Malthus believed that population would increase at a geometric rate and the food supply at an arithmetic rate.

Malthusian population theory was eventually dismissed for its pessimism and failure to take into account technological advances in agriculture and food production. [Source]

Conclusion

How should theories be taught? By this post, I only intend to question the current teaching and understanding of Malthus’ theories. Also, I wish to stress the importance of understanding and studying the ‘context’ (historical, political, social, cultural,etc) of a theory.

Now, economists (positive economics) are busy using scientific methods so as to universalise theories rather than provide solutions to hunger, poverty, unemployment and other socio-economic problems.

To sum up, Malthus stressed on the need to keep population and food production in such a way that everyone would be fed. I believe that this still holds true across the globe as one of the main concerns of economics.

Further Reading

1) 1) 1) Darwin and Malthus

2) 2) 2) Is India falling into the Malthusian trap?, C. J. Punnathara, The Hindu Business Line, April 9, 2008.

3) 3) 3) Malthus, the false prophet, May 15th 2008, The Economist.

4) 4) 4) The International Society of Malthus (further links from the society)

5) On GM Food and GM Mosquitoes

Economics Education: The Indian Context

Economics is viewed in most schools, colleges (Management institutes as well) and universities as a monolithic enterprise. It comprises mainly Microeconomics and Macroeconomics and uses Econometrics and Mathematical Economics as tools to understand the economy. Interestingly, tools like philosophy, history, sociology, anthropology lie forgotten. Or probably they are not viewed as tools anymore. Or they are not scientific enough!

This post deals with the dominant perception of Economics within India and how these perceptions adversely affect the spirit of economics in particular and of scientific inquiry in general.

Courses like History of Economic Thought are extended to include Classical Political Economy, Marxian Economics, etc. They are taught as outdated ideas and not as relevant approaches in understanding the economy. This is visible from the responses of students when works of Adam Smith, David Ricardo, Karl Marx etc are mentioned. I shall discuss Malthus in this post and in the next post, I shall discuss some of the theories of Marx.

Unfortunately, Malthus is known only for his ‘bad’ population theory. Interestingly enough, all that Malthus [1798] said was “that population, when unchecked, increased in a geometrical ratio, and subsistence for man in an arithmetical ratio.

Let us examine whether this position be just. I think it will be allowed, that no state has hitherto existed (at least that we have any account of) where the manners were so pure and simple, and the means of subsistence so abundant, that no check whatever has existed to early marriages, among the lower classes, from a fear of not providing well for their families, or among the higher classes, from a fear of lowering their condition in life. Consequently in no state that we have yet known has the power of population been left to exert itself with perfect freedom.” (Italics added)

Such an argument is what philosophers of science classify as a ‘thought experiment’. But mainstream economists classify this as a theory which has provided wrong predictions.

Thought experiments are devices of the imagination used to investigate the nature of things. And in our own time, the creation of quantum mechanics and relativity are almost unthinkable without the crucial role played by thought experiments. [Brown 2007] If one were to discredit and disregard Malthus’ theory, then there is no reason why the theory of perfect competition should be considered in Economics at all. The issue is that, there is hardly any work being done in methodological issues pertaining to economics and on the structure of a good economic theory, therefore one definitely needs to consider each and every theory in its own context. By context I refer to the historical background and the general argument that is being put forth.

Philosophical debates within Economics are very essential for the growth of both the disciplines, but more significant for economics. Methodological and epistemological issues are not commonly discussed in economics. This is very necessary because economics, economists and economies are ever growing in importance. Their policies have far reaching effects. And if they are not constructed in the right spirit, the objectives of the policy might not be fulfilled at all. The Indian budget 2008-09 is one such example. None of the Indian universities have a course pertaining to the Philosophy of Economics in its Masters’ courses. This shows the importance it has received vis-a-vis econometrics and game theory.

Also, economics claims to be a science and Professor Peter Englund, Secretary of the Economics (Nobel) Prize Committee thinks so as well when he says “In all relevant respects the committee understands and treats economics as a field of science.” I see it as a shirking away of economics from questioning itself- its methodology and its knowledge.

It is primarily this attainment of a scientific nature by mainstream neoclassical economics that is bringing doom to the people constituting the economy. The present analysis in mainstream economics is not only ahistorical but also asocial. Economics needs to understand its origins and its epistemology. It ought to be a pluralistic enterprise. And let theoretical anarchism prevail because “it is more humanitarian and more likely to encourage progress.” [Feyerabend 1975]