Sunday, 7 October 2012

Are ignorant opinions worth hearing?

Economist John Quiggin got some flak for a post on Crooked Timber posing the question 'who needs a navy?' In particular, some folk thought he lacked the necessary expertise to have a meaningful opinion on a subject best left to the experts. Here's part of his reply:

First, there’s the question of specialist expertise. Criticism of the original post relied heavily on the claim that specialist knowledge is critical here, and that as a non-expert I should defer to people who with better knowledge of things like the classification of battleships. Much the same response is often made by economists when arguing about issues like macroeconomics and finance. The problem in both cases is that, unlike the case with the natural sciences, it’s perfectly reasonable to argue that the dominant view of the experts is wrong.

Macroeconomists and finance theorists mostly failed to predict the global financial crisis, and disagree violently about the appropriate policy response. I’ve argued at length that the views that have been dominant in these fields since the 1970s are mostly wrong, and have received responses quite similar to those of the naval experts in this case. Looking at the track record of military and naval experts, it doesn’t seem to me that it’s any better than that of economists, rather the opposite. So, I’m unconvinced by the view that this is a field where expertise is a guarantee of correctness, or even positively correlated with correctness.

In the comments, somebody turned the question round to 'who needs economists?':

I would read with slightly more charity a post suggesting that most if not all funding for university departments of economics since, say, 1960 has been not only a waste of money but actually actively harmful. At least most warships have spent most of their careers doing nothing worse than floating around idly being repainted. The same cannot be said of the economics profession, which has caused a lot more misery and avoidable suffering to a lot more people in the last 30 years than every aircraft carrier in the US Navy.
Quiggin and his critics focus on experts getting stuff wrong ('unlike the case with the natural sciences, it’s perfectly reasonable to argue that the dominant view of the experts is wrong'). Evidence of economic policies failing, or of economists failing to agree on the big questions in their discipline is easy to find. History books are full of experts' failed military plans. Is it the experts' fault?

Two initial possibilities occur to me - either the majority of economists (and military theorists?) are less competent than natural scientists, or they are just as talented, but the problems they're trying to understand are more complex and intractable than the problems which have been already cracked by successful scientific theories. Maybe economics is like a particularly hard branch of the natural sciences, for example meteorology, where what's going on remains too irreducibly complex for anyone to give accurate long range predictions about important things, like where and when the next freak storm will hit.

I think that another factor is just as important as competence or complexity - inherent bias. Economics and military planning are too bound up with people's self-interest to be objective descriptions of how the world works, as opposed to ideologies about how it ought to work. It's harder to take an objective view about things that affect your prospects or position in society. An expert opinion about the nature of electromagnetism, or the age of the universe has nothing to do with the price of fish, so most non-experts don't fret about such things.An expert with a theory about what the correct level of taxes should be, whether something approaching full employment is achievable or desirable, the relative efficiency of private versus public heath care, which things the state should take care of and which should be left to the free market, immigration, free trade or anything which would directly affect people's lives, is bound to upset somebody.
And what exactly is 'objectivity' in economic terms? Not all economic decisions are zero sum games, but change almost anything and there will be relative winners and losers. What looks rational and efficient from where you're sitting might be a disaster for my prospects and vice versa, so we're into political choices about how to fairly share out the gain or the pain and then making further political decisions in response to the results of those choices feeding back into the system. Economic reality is yesterday’s political choice.

It seems to me that the size and shape of the military is a sub branch of economics. You've got the same allocation of finite resources, ideological differences about what the military are for and competing interests (the military vs. the rest of the economy and different branches of the military vs. each other).

In most fields, an expert opinion is worth more than an ignorant one (although there are exceptions where an ignorant, but bright, outsider with a fresh viewpoint might have some insights to trump the narrow technical knowledge of an expert). But there are some subjects that are so purely ideological that ignorance of the subject matter needn't invalidate anybody's opinion. In my opinion, theology sits on that end of the spectrum, resting as it does on a priori beliefs about subject matter that may not even exist. As far as I'm concerned, the theological opinion of any random person in a bus queue is no more unlikely to be correct than that of the most learned theologian on the planet. At the other end of the spectrum lie things like quantum mechanics, computer programming, string theory, plumbing, speaking a language fluently, mathematics, playing a musical instrument, brain surgery and rocket science,* where you just won't understand and things won't work if you don't know your stuff.

Economics has a sounder empirical basis than theology and an infinitely more technically rigorous superstructure, but it's also built on foundations of ideology and value judgements. Unlike fields 'where expertise is a guarantee of correctness, or even positively correlated with correctness.' Which is why I don't think that we non-economists should necessarily shut up and defer to the experts, (or that economists should necessarily shut up and defer to military experts who, for all their technical expertise can be just as driven by ideology and bias).

Sei Sh┼Źnagon included this in her list of hateful things:

A man who has nothing in particular to recommend him discusses all sorts of subjects at random as if he knew everything.

I liked the phrase so much that used it as the strapline for this blog before changing to something a bit more surreal. I'm fine with people with nothing in particular to recommend them discussing all sorts of subjects as though they knew everything. When discussing some subjects, such as economics, their opinions might turn out to be as interesting and valid as the experts'. I might take random opinions on topics like brain surgery with a bigger pinch of salt, though.

*So-called - as far as I can see it's rocket engineering, in the same sense that the Hollywood's stereotypical 'mad scientist' is really a mad engineer.