Tuesday, July 24, 2018

Pitfalls of history - I

A politician needs the ability to foretell what is going to happen tomorrow, next week, next month, and next year. And to have the ability afterwards to explain why it didn't happen. - Winston Churchill

In the controversy over the film 'Padmavat', there were comments that 'history is being distorted' or that 'historical facts are being twisted'. I don't have much idea about either the film or the historical character so that is not what this post is about. These comments seem to give the impression that history about an event or a personality is fixed for all time to come. But this is not true. First of all, there is nothing called ‘correct’ history. There can only be views of the past, some of which approximate more clearly to what actually may have happened because of the evidence they draw upon and the quality of their logic and analysis.

Our perception of the past changes as and when the evidence increases and when the methods for interpreting the evidence improves. Some archaeological expeditions require scientific expertise like DNA analysis and radio-carbon dating so people with knowledge about these scientific fields must be part of the group.  New methods of data analysis and new sources throw fresh light on old incidents. Quite often the new views are slow to trickle down to the general public, who  tend to think that what they leaned in high school history books is unchangeable. In The Black Swan, Nassim Nicholas Taleb tells of three problems in the human mind, which he calls 'the triplet of opacity', which affect our perception of history:

1. The illusion of understanding: People think the world is more understandable, explainable and predictable than it really is. But there are many unexpected factors which impact events.These factors seem predictable in retrospect giving rise to this illusion.

2. History seems more organised and structured in textbooks than it really was. When I was reading about the 70's and beyond in Ramachandra Guha's book India after Gandhi (which is a good book), I seemed to have been living in the midst of chaos. I remember most of the dark headlines but they occurred far away from where I lived. Historians have to write about many incidents spread over vast expanses of space and time in a limited number of pages which results in distortion of the reality.

3. Over-reliance on experts: Philip Tetlock, a psychologist at the University of California, Berkeley selected 284 people who made their living "commenting or offering advice on political and economic trends," including journalists, foreign policy specialists, economists and intelligence analysts, and began asking them to make predictions. Over a couple of decades, he asked them to rate the probability of outcomes of several questions: Would George Bush be re-elected? Would apartheid in South Africa end peacefully? Would Quebec secede from Canada? Would the dot-com bubble burst? Overall he had over 80,000 predictions.

How did the experts do? When it came to predicting the likelihood of an outcome, the vast majority performed worse than random chance i.e, they would have done better picking their answers blindly out of a hat. Liberals, moderates and conservatives were all equally ineffective. Most of the subjects had post-graduate degrees but they were mostly useless when it came to forecasting. Even in the region they had most knowledge of, the experts were not much better than non-specialists.

The main reason for the inaccuracy has to do with overconfidence. Because the experts were convinced that they were right, they tended to ignore all the evidence suggesting that they were wrong - they had an enhanced illusion of their skill. Those with the most knowledge were the least reliable. This is because these experts were cocooned in their area of specialization and tended to view the world through a narrow lens, what Nassim Nicholas Taleb calls 'the philistinism of the over-specialized scholar'. It is like the blind who touch different parts of an elephant and conclude that it is like a rope, a pillar, etc.

Tetlock also found that the experts were resistant to admitting error when it was pointed out to them, offering a number of excuses for their mistakes. The problem is that the over-specialized expert who can come up with the catchy one-liner is more likely to be invited to TV studios since  he is more interesting to listen to than the expert who uses a lot of 'ifs' and 'buts' even though the latter may be closer to the truth. The preferred expert will be the one who gives short, snappy answers to a screaming host who demands, 'India wants to know.'

A safe rule of thumb to follow is to ignore the views of the experts who sound very confident about their forecasts. As Kahneman says in his book, Thinking, Fast and slow, 'The first lesson is that errors of prediction are inevitable because the world is unpredictable.  The second is that high subjective confidence is not to be trusted as an indicator of accuracy (low confidence could be more informative).

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