Sraffa: The Origins of ‘Marginal’ Analysis

Since the advent of the ‘marginal’ method, the doctrines of the old classical economists have been submerged and forgotten. It is this standpoint that Sraffa revives in his 1960 book Production of Commodities by Means of Commodities. Being third in the series of posts [Post 1; Post 2] on Sraffa, this post examines the origin of the ‘marginal’ method and its subsequent (mis)use by the neoclassical economists. The posts concludes with a brief mention of how history of economic thought is important so as to place theories in a proper context.

In the preface of his book, Sraffa points out that in a system of production where the scale of an industry or proportions of factors of production remained unchanged, one would not be able to locate marginal product and marginal cost. To put it differently, marginal analysis is done by considering ‘potential change’. That is, we try to find out variations in equilibrium quantities and prices with respect to infinitesimal changes in the neighbourhood. [Bharadwaj 1986, p 39]

What we do not pay adequate attention to, is that the most familiar case of ‘marginal analysis’ is that of the product of marginal land (also known as no rent land) in agriculture, when lands of different qualities are cultivated side by side. This refers to the well known differential rent theory of David Ricardo. In fact, it is the case of diminishing marginal returns on land which is at the junction of the ‘fundamental methodological shift from classical to equilibrium theory’. [Bharadwaj 1986, p 40] This can be understood only through a discussion of ‘extensive’ and ‘intensive’ margins.

Cultivation on lands of different qualities is visualised as the outcome of a process of ‘extensive’ diminishing returns. On the other hand, successive use of more output producing techniques refers to the process of ‘intensive’ diminishing returns. [Sraffa 1960, p 76] In the case of ‘extensive’ margins in cultivation, ‘the rents can directly worked out on the basis of the single observed situation.’ [Bharadwaj 1986, p 41] Whereas, in the case of ‘intensive’ margins, the calculation of rent requires a quantitative change in the situation. That is, successive doses of labour and ‘capital’ need to be added to the land. And, a further assumption is made on the nature of these ‘doses’. These ‘doses’ are considered to be homogeneous. As Krishna Bharwadwaj explains: ‘At any moment of observation, no dose is distinguishable from each other. No ‘marginal product’ can, therefore, exist in this case without introducing potential change.’ [Bharadwaj 1986, p 42]

Thus, it is the Ricardian theory of rent which provided the basis for the neoclassical theory of distribution by providing an inverse relationship between successive doses of labour and ‘capital’ and their remuneration. This theory of Ricardo was intended to explain the origin of rents. In the hands of later authors, this was generalised to labour and ‘capital’. Hence, we see the inverse relation between ‘capital intensity’ and rate of profit in microeconomics textbooks of today.

From this excursion into the Ricardian theory of rent, two aspects are very clear. First, the concept of ‘marginal’ or ‘margins’ was used exclusively in the domain of cultivation. In ‘intensive’ cultivation, it is obvious that the output would increase only until a certain point, owing to the quality of that piece of land. Whereas, in the case of ‘extensive’ cultivation, the output would increase till all the acres of land are cultivated- notice the scarcity element here. What is not clear is the rationale of extending such an analysis into the area of manufacturing! Also, it is well accepted that land is scarce; but, is ‘capital’ or produced commodities scarce in a similar way’

No book of microeconomics mentions the origins of the famous ‘marginal’ analysis. And this method is so entrenched in the profession, that it is almost impossible to throw it away. It is in this context that other conceptual frameworks, that pay more attention to the changing historical conditions, assume importance. Probably, we need to revisit earlier theories and theorists not just for their own sake but for our sake as well in throwing light on contemporary issues. Sraffa’s work has inspired a lot of work on the history of economic thought, which will be summarised in a later post.

References

Bharadwaj, Krishna (1986), ‘Classical Political Economy and Rise to Dominance of Supply and Demand Theories‘, Universities Press: Calcutta.

Sraffa, Piero (1960), ‘Production of Commodities by Means of Commodities: Prelude to a Critique of Economic Theory‘, Cambridge University Press: Cambridge.

On Prices/Values

Economics, rather Political Economy attempted at providing a coherent theory of value. Economists such as Adam Smith, David Ricardo, Karl Marx, etc are associated with a ‘theory of value’. Currently, in economics, ‘value’ is not discussed in courses of relevance. However, students are exposed to value theories such as labour commanded, labour embodied and so on.

This post is the second in the series of posts ‘On Prices’. This posts attempts at clarifying concepts such as values, prices and costs of production. Note that all prices which are mentioned in economics textbooks (microeconomics, introductory economics, principles of economics, etc) pertain to relative prices or long-run prices. That is, they do not talk about market prices. The reason for this is because it is assumed/believed that market prices tend to fluctuate or hover around these relative prices. In other words, given a particular technology, these relative prices, in some sense, reflect the interrelationships in the economy. Hence, these natural/normal proces are studied in order to understand the workings of a capitalist economy.

Let me start with what is usually taught in various economics and management institutes across the world and even in higher secondary schools. Prices are determined by the interaction of supply and demand. This implies that an excess dmand leads to a price hike. Let us look at an example: Suppose I go to a toy shop and ask for a Meccano set and immediately, another customer asks for the same set. But, the shop has only one Meccano set. Will the price of the Meccano set increase’ Is such an explanation intuitive or common sensical’ This example talks of an isolated case.

Economics is interested in the formation of a spectrum of prices at the level of the economy. Interestingly, macroeconomics has nothing to offer on price formation. Often, or rather everywhere in the world, economics is taught as microeconomics and macroeconomics. The interdependence and interrelationship present in any economy is inadequately addressed. The closest one comes is probably through the ‘circular flow’ diagram which highlights the role of the firm as well as the households. In this diagram, the complex and strutural interdependence is oversimplified to that of a 2-way interaction between the firm and household via labour market, capital market, etc and the state is shown to play the role of a facilitator. The interrelated production structures goes unnoticed or is seldom mentioned. Why is this important’

How can prices be determined’ (The dominant factor will be mentioned.)

1) Demand & Supply – The prices which are determined in this way are the prices of vegetables and fish, prices of shares in the stock markets, price of real estate, etc. In some sense, these prices can be said to be supply determined. For, these commodities are more often subject to variations in supply than in demand.

2)Costs of Production – An alternative view which is present in the literature is that the prices of commodities are prices according to the prices paid to the means of production as well as adding a certain percentage as profit. According to Kalecki, the percentage depends on the monopoly power of the firm. What if the firm’s final product is an input for another firm’ Will this affect the price of the product’ This aspect is often forgotten in economics.

This forgetfulness is strongly associated to the lack of importance mainstream and even some heterodox economic theories gives to interrelationships in the production structures in an economy. To have a glimpse into this, one needs only to look at an Input-Output table.

If we assume (correctly) that production structures in a capitalist economy are interrelated then we can conceptually distinguish goods/services into – Basics and Non-Basics. [Sraffa 1960] Basic goods are those goods which directly or indirectly enter into the production of every commodity in the economy including its own. An obvious example would be foodgrains because they are needed for labourers and labour is required in all activities. And a tax on a basic good will have cascading effects on the prices of all the goods in the economy.

I shall quote Sraffa to point out the significance of accepting and studying interdependence.

The exchange-ratio (or relative prices) of non-basics is “merely a reflection of what must be paid for means of production, labour and profits in order to produce them – there is no mutual dependence.” [p 8, Sraffa 1960]

“But for a basic product there is another aspect to be considered. Its exchange-ratio depends as much on the use that is made of it ….” [pp 8-9, Sraffa 1960]

It is because of these issues that Sraffa uses values/prices than costs. Also, Sraffa knew that in an economy, “costs of production cannot be measured independently of, and prior to, the determination of the prices of products.” [p 9, Sraffa 1960] To conclude, dan we therefore think that Sraffa’s analysis is similar to the neoclassical analysis of price using demand and supply’

In brackets, Sraffa writes “one might be tempted, but it would be misleading, to say that ‘it depends as much on the Deamnd side as on the Supply side.'” [p 9, Sraffa 1960]

References

1) Kalecki, Michal (1971), Costs and Prices, in Selected Essays on the Dynamics of the Capitalist Economy 1933-1970, Cambridge University Press, pp. 43-61.
2) Sraffa, Piero (1960), Production of Commodities by Means of Commodities, Cambridge University Press.

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

The Political Economy of Singapore

 

The Political Economy of Social Control in Singapore
Christopher Tremewan
1996

Excerpts

Singapore has been widely seen as an economic miracle, a veritable and contentment.’

The Singapore state is the exclusive or major provider of infrastructure (utilities, communications, media, industrial estates, port and airport services) and of social services (housing, health and education). It is the country’s largest employer, it sets wage levels, regulates labour supply and controls all unions. It is the main actor in the domestic capital market, runs giant state enterprises, a trading company and joint ventures with foreign capital. It also directs the apparatus of state coercion: the police and the internal security organizations, the courts and the prisons and a large military force.’

‘..many people are constantly aware of the political limits on personal behaviour imposed by the state.’

‘..the singular characteristic of social control in Singapore is its success in producing political loyalty and cooperation among the majority of the population.’

‘The wealthiest ten per cent of Singapore households take approximately 30 per cent of total income, while the poorest 10 per cent are left with 2 or 3 per cent of total income.’

‘Neither the inequality nor the comprehensive system of social control in Singapore are obvious to the casual observer.’

‘The increased consumption of the services and consumer goods has had the ideological effect of Singaporeans believing that they have more control over their lives rather than less.’

‘the main political effect of the housing policy was the production of a working class dependent on wage labour to pay for it. The former was achieved through the physical destruction of all other forms of cheap housing and through forced settlement.’

Conclusion

Though Singapore has achieved great growth rates, I wonder if there is ‘freedom’ in that country. Or are high growth rates alone sufficient’ Read this book to know more.

Further Reading

1) Singapore Diary-Part 3 By E Pradeep

2)On Singapore-Binu Ninan