Or is economics inherently right wing?
I noted in passing in an earlier post that Pareto efficiency was obviously not a value free criteria. So those who argue that economists should only look for Pareto improvements – changes where no one is made worse off – are making a value judgement. One, and only one, of its implicit normative assumptions is that inequality does not matter. For others see, for example, Elizabeth Anderson (pdf, HT Anon). Now you could argue that an assumption that inequality does not matter intrinsically is at least internally consistent with the conventional assumption that personal utility depends only on personal variables. However as that assumption is clearly incorrect, this is a rather weak defence.
(You could also reasonably argue that Pareto improving increases in inequality could have a negative impact on the personal variables of others that conventional economic analysis ignores. So, for example, rising incomes of the 1% - even if this initially comes from just increasing the size of the pie - allows that 1% greater political power, which they will subsequently use to redistribute income away from the 99%.)
This is hardly a new point. For just two recent examples of other posts saying the same thing: Richard Serlin here, and Ingrid Robeyns here. It only has to keep being said because too many students are taught that economists like the Pareto criteria because it is value free. One of the comments to that second post says that the task should not be to “import liberal or left-wing moral philosophy into economics. It’s to scrub right-wing, libertarian moral philosophy out of it.” Well, in my usual moderate manner, I’d say we should at least expose it.
A more sophisticated defence of Pareto optimality is the second welfare theorem, which says that we can separate issues of distribution from issues of allocative efficiency. So, if some Pareto improving measure only makes the 1% better off, we can go ahead with it and deal with any reduction in social welfare generated by additional inequality using lump sum transfers. One obvious problem with this idea is that there are no lump sum transfers. Another is that we do not as a society decide at some date every year what the optimal distribution of income to implement is. In practice the only chance of reversing any inequality created by a Pareto improving measure is to use compensation alongside that measure, but then agents will recognise this connection which in turn will influence incentives.
The only possibly original point I wanted to make here is that the absurdity of restricting policies to Pareto improvements becomes immediately apparent if we think about government debt. Measures to reduce currently high levels of debt will almost certainly make current generations worse off, because they will have to pay the taxes (or whatever) to get debt down. Yet I do not often hear people arguing that we have to let debt stay high because the government can only implement Pareto improvements. If you think about it for a second, restricting government debt policy to Pareto improvements would be a sure fire recipe for deficit bias.
While this may be obvious, textbooks still make a big deal of dynamic inefficiency. This is the idea that the amount of productive capital in society can be too high, so that too much output is going to preserving that level of capital (replacement investment to offset depreciation etc), and not enough to consumption. If that is true, then if the current generation saves less, everyone can be made better off. Government intervention to discouraging saving would be a Pareto improvement: the current generation consumes more because they save less, but future generations consume more because less output needs to go to replacement investment.
The symmetrical case is where there is too little capital, which also reduces long run consumption compared to what could be achieved. Yet the implication in many textbooks is that this case is not one we should worry about, because to change it (by raising saving) would make the current generation worse off and is therefore not a Pareto improvement. The discussion in Romer, for example, is all about whether economies are dynamically inefficient rather than sub-optimally small. We don’t think this way about government debt, so why should we when it comes to productive capital?
Why is there this emphasis on only looking at Pareto improvements? I think you would have to work quite hard to argue that it was intrinsic to economic theory - it would be, and is, quite possible to do economics without it. (Many economists use social welfare functions.) But one thing that is intrinsic to economic theory is the diminishing marginal utility of consumption. Couple that with the idea of representative agents that macro uses all the time (who share the same preferences), and you have a natural bias towards equality. Focusing just on Pareto improvements neutralises that possibility. Now I mention this not to imply that the emphasis put on Pareto improvements in textbooks and elsewhere is a right wing plot - I do not know enough to argue that. But it should make those (mainstream or heterodox) who believe that economics is inherently conservative pause for thought.