Are consumers ‘rational’ is the sense of trying to maximise consumer surplus? In some circumstances the answer is yes. When we go shopping we do generally try to get best value for money, where value is defined in terms of utility. With limited incomes, we don’t want to waste money. If we were offered two baskets of goods costing the same amount, we would generally choose basket A if its contents gave us more utility than basket B.
So why do we frequently buy things that are bad for us? Take the case of food. Why do we consume junk food if we know fresh produce is better for us? To answer this we need to look a little closer at the concept of utility and what motivates us when we consumer things. The following article does just that. It reports on writings of Michael Pollan. Pollan looks at our motivation when choosing what and how much to eat. For much of the time our choices are governed by our subconscious and by habit.
“Millions of humans, while believing they govern their actions with conscious intelligence, clean every morsel from their dinner plates, mainly because their parents told them to. And we do this even if we don’t particularly like the food on the plate and even if we know we should be eating less of it. Unthinkingly, we follow a habit we would condemn if we looked at it clearly.”
You mar what you eat and the politics of Michael Pollan National Post (Canada), Robert Fulford (18/1/10)
- What is meant by ‘rational behaviour’? Is it reasonable to assume that people are rational in most circumstances?
- Is eating junk food consistent with the attempt to maximise consumer surplus?
- How relevant is the principle of diminishing marginal utility in explaining the amount of junk food we eat?
- To what extent are the problems that Pollan identifies examples of (a) imperfect information; (b) irrationality?
- What does people’s eating behaviour reveal about their preferences for the present over the future and hence their personal discount rate?
- What are the policy implications of Pollan’s analysis for governments trying to get people to eat more healthily?
The health of an economy is generally measured in terms of the growth rate in GDP. A healthy economy is portrayed as one that is growing. Declining GDP, by contrast, is seen as a sign of economic malaise; not surprisingly, people don’t want rising unemployment and falling consumption. The recession of 2008/9 has generally been seen as bad news.
But is GDP a good indicator of human well-being? The problem is that GDP measures the production of goods and services for exchange. True, such goods and services are a vital ingredient in determining human well-being. But they are not the only one. Our lives are not just about consumption. What is more, many of our objectives may go beyond human well-being. For example, the state of the environment – the flora and fauna and the planet itself.
Then there is the question of the capital required to produce goods and maintain a healthy and sustainable environment. Capital production is included in GDP and the depreciation of capital is deducted from GDP to arrive at a net measure. But again, things are left out of these calculations. We include manufactured capital, such as factories and machinery, but ignore natural capital, such as rain forests, coral reefs and sustainable ecosystems generally. But the state of the natural environment has a crucial impact on the well-being, not only of the current generation, but of future generations too.
In the video podcast below, Professor Sir Partha Dasgupta, from the Faculty of Economics at the University of Cambridge and also from the University of Manchester, argues that the well-being of future generations requires an increase in the stock of capital per head, and that, in measuring this capital stock, we must take into account natural capital. In the paper to which the podcast refers, he argues “that a country’s comprehensive wealth per capita can decline even while gross domestic product (GDP) per capita increases and the UN Human Development Index records an improvement.”
Nature’s role in sustaining economic development (video podcast) The Royal Society, Partha Dasgupta
Nature’s role in sustaining economic development Philisophical Transactions of the Royal Society B, vol 365, no. 1537, pp 5–11, Partha Dasgupta (12/1/10)
GDP is misleading measure of wealth, says top economist University of Manchester news item (21/12/09)
Economics and the environment: Down to earth index Guardian (28/12/09)
- Why might a rise in GDP result in a decline in human well-being?
- In what sense is nature ‘over exploited’?
- What is meant by ‘comprehensive wealth’ and why might comprehensive wealth per capita decline even though the stocks of both manufactured capital and human capital are increasing?
- What is meant by ‘shadow prices’ in the context of natural capital?
- How might economists go about measuring the shadow prices of capital?
- What factors should determine the rate of discount chosen for projects that impact on the future state of the environment?
Al Gore’s contribution to the global climate change debate is not in question and he has, along with the IPCC, been awarded the 2007 Nobel Peace Prize for his work in raising awareness. If you haven’t seen his film “An inconvenient truth” then do get hold of the DVD – it may just be the most interesting PowerPoint presentation you will ever see! However, does he really understand the nature of the debate? The article below suggests that he has not yet taken account of the most fundamental trade-off in dealing with climate change – the trade-off between our own quality of life and that of our descendants in the future.
Save the earth in six hard questions MSN Slate (22/10/07)
||Explain what is mean by a trade-off “between the quality of our own lives and the quality of our descendants’ [lives]”.
||What is meant by the term ‘risk-averse’ and how is this relevant in the climate change debate?
||Consider the questions raised by the article. Discuss how relevant the conclusion reached is in the light of these questions.