We rely on experts for so many things in life... Unfortunately, experts are often wrong.

Everyone is worried about Ebola, even the experts. Those are the same experts who had, until recently, told us not to be apprehensive when the outbreak in West Africa made its way to the Western world.

The Center for Disease Control in the United States had repeatedly assured the public that modern health care in the developed world can handle the outbreak.

But were they right?

With this week’s death of a UN worker in Germany, a second case reported in Texas, and five airports as well as London’s Heathrow Airport beginning Ebola screening for certain flights (with Gatwick and Eurostar terminals set to follow in coming days), the experts are beginning to change their tune. The World Health Organization is now describing the outbreak as "the most severe, acute health emergency seen in modern times.”

We rely on experts for so many things in life, from doctors capably diagnosing and treating illness to defence analysts assessing terrorist risk to accountants that audit corporate finances to assure investors that all is above board.

Unfortunately, experts are often wrong.

Financial mistakes

Take auditors, whose entire purpose — mandated by law – is to carefully evaluate the way a company accounts for its activities. Without an auditing function, how could investors feel confident that the enterprise in which they are placing their trust, and their money, is legitimate?

Alas, auditors are remarkably fallible and for very human reasons. Is it a coincidence that the auditing team from Arthur Andersen that worked on the Enron account consisted of numerous former employees of Enron? And that these same accountants continued to sign off on increasingly questionable accounting practices quarter after quarter? I make no aspersions as to whether the accountants behaved in an illegal, or even unethical manner. My point is that the familiarity of overseers with the client could have served to somehow colour their thinking in a way that disrupted their ordinary diligence and competence.

Surely something quite analogous occurred among rating agencies in the run up to the financial crisis of 2008. These agencies — Standard and Poor’s, Moody’s, Fitch — consistently rated bundles of subprime mortgages sold by financial institutions with their highest rating of safety. And it is this assurance that enabled a market to form to trade in subprime.

These two stories have one more thing in common – the people whose job it was to provide oversight were paid by the companies they had jurisdiction over. Again, it’s not that the experts at Enron or S&P set out to be negligent, it’s just that they did. Self-interest, which is at the heart of the matter, often operates at a subconscious level. The people I’m writing about may well be enraged to be reading this, because they truly believe they didn’t behave in an unethical manner. And that may be so.

What experts – indeed, all of us – don’t often appreciate is how easy it is to think we’re absolutely doing the right thing when in fact we’re not.

When they get it wrong

Experts can be wrong for many other reasons.

What of the vaunted Secret Service in the US, the legendary government agency responsible for protecting politicians? How could a potential assailant gain access to the White House, running from room to room before being apprehended? While there will be investigations, I’m willing to bet the problem has more to do with culture than competence. Most experts come wrapped up in an organisation, complete with bureaucratic infighting, misaligned incentives and poor leadership. It’s tough to be an effective expert when the detritus of organisational life surrounds you.

So experts have flaws, some self-inflicted and some driven by context. But let’s be careful not to over react. What would life be if there were no experts?

For one thing, even worse than the state of affairs we’re in now. Expertise comes from careful investigation, and sometimes experience, designed to yield insights of value to some part of society.

If there were no experts, for example, many people would have no reason to be concerned about climate change. The fact that some people insist in 2014 that carbon dioxide emissions are not related to temperatures on Earth could  be a classic example of what happens when thinking is uninformed by expert knowledge.

In a world without experts, decisions are based on ideology, hardly the basis for careful analysis.

All of which is to say that when it comes to the Ebola threat, I am putting my trust in the modern health-care establishment, not because I think they are definitely correct, but because that’s all we’ve got.

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