In an interview with EUROPP’s editor Stuart Brown and British Politics and Policy at LSE’s editor Joel Suss, Thomas Piketty discusses the rise in income and wealth inequality outlined in his book, Capital in the Twenty-First Century, and what policies should be adopted to prevent us returning to the kind of extreme levels of inequality experienced in Europe prior to the First World War. Professor Piketty recently gave a lecture at the LSE, the video of which can be seen online here.

Your research has shown that inequality is rising and that without government action this trend is likely to continue. However, are we correct to assume that inequality is a fundamentally negative development in terms of its consequences on society?

There is no problem with inequality per se. In actual fact, up to a point inequality is fine and perhaps even useful with respect to innovation and growth. The problem is when inequality becomes so extreme that it no longer becomes useful for growth. When inequality reaches a certain point it often leads to the perpetuation of inequality over time across generations, as well as to a lack of mobility within society. Moreover, extreme inequality can be problematic for democratic institutions because it has the potential to lead to extremely unequal access to political power and the ability for citizens to make their voice heard.

There is no mathematical formula that tells you the point at which inequality becomes excessive. All we have is historical experience and all I have tried to do through my research is to put together a large body of historical experience from over twenty countries across two centuries. We can only take imperfect lessons from this work, but it’s the best that we have. One lesson, for instance, is that the kind of extreme concentration of wealth that we experienced in most European countries up until World War One was excessive in the sense that it was not useful for growth, and probably even reduced growth and mobility overall.

This situation was destroyed by World War One, the Great Depression, and World War Two, as well as by the welfare state and progressive taxation policies which came after these shocks. As a consequence, wealth concentration was much lower in the 1950s and 1960s than it was in 1910, but this did not prevent growth from happening. If anything, this probably contributed to the inclusion of new social groups into the economic process and therefore to higher growth. So one important historical lesson from the 20th century is that we don’t need 19th century-style inequality to generate growth in the 21st century, and we therefore don’t want to return to that level of inequality in Europe.

How would you respond to those who doubt whether there is sufficient evidence to draw this kind of conclusion?

This will always be an imperfect inference because we are in the social sciences and we should not have any illusions about what is possible. We can’t run a controlled experiment across the 20th century or replay the century as if World War One and progressive taxation never occurred. All we have is our common historical experience, but I think this is enough to reach a number of fairly strong conclusions.

The lesson we have already mentioned – that we don’t need the kind of extreme inequality of the 19th century in order to have economic growth – is simply one imperfect lesson, but there are other important lessons if you look at, for instance, the rise of inequality in the United States over the past 30 years. For example, is it useful to pay managers a ten million dollar salary rather than only one million dollars? You really don’t see this in the data: the extra performance and job creation in companies which pay managers ten million dollars rather than one. In the United States over the past 30 years almost 75 per cent of the aggregate primary income growth has gone to the top of the distribution. Given the relatively mediocre productivity performance and the per capita GDP growth rate of 1.5 per cent per year, having nearly three quarters of that going to the top isn’t a very good deal for the rest of the population.

This will always be a complicated and passionate debate. Social science research is not going to transform the political conflict over the issue of inequality with some kind of mathematical certainty, but at least we can have a more informed debate using this historical cross-country evidence. Ultimately that is all my research is aiming to do.

What specific policies can be used to prevent us returning to the kind of extreme levels of inequality you have discussed?

There are a large number of policies which can be used in combination to regulate inequality. Historically the main mechanism to reduce inequality has been the diffusion of knowledge, skills and education. This is the most powerful force to reduce inequality between countries: and this is what we have today, with emerging countries catching up in terms of productivity levels with richer countries. Sometimes this can also work within countries if we have sufficiently inclusive educational and social institutions which allow large segments of the population to access the right skills and the right jobs.

However while education is tremendously important, sometimes it’s not sufficient in isolation. In order to prevent the top income groups and top wealth groups from effectively seceding from the rest of the distribution and growing much faster than the rest of society, you also need progressive taxation of income and progressive taxation of wealth – both inherited and annual wealth. Otherwise there is no natural mechanism to prevent the kind of extreme concentration of income and wealth that we’ve seen in the past from happening again.

Most of all, what we need is financial transparency. We need to monitor the dynamics of all of the different income and wealth groups more effectively so that we can adapt our policies and tax rates in line with whatever we observe. The lack of transparency is actually the biggest threat – we may end up one day in a much more unequal society than we thought we were.

A video of Thomas Piketty’s recent LSE lecture is available here

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Note: This article gives the views of the interviewee, and not the position of EUROPP – European Politics and Policy, nor of the London School of Economics.

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About the interviewee

Thomas Piketty – Paris School of Economics
Thomas Piketty is Professor of Economics at the Paris School of Economics. He is the author of Capital in the 21st Century (Harvard University Press, March 2014).

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