the second world war
a german prison camp and this
the problem is that the men under his care
are suffering from an excruciating and debilitating condition that archie doesn 't really understand the symptoms are this horrible swelling up of fluids under the skin but he doesn 't know whether it 's an infection whether it 's to do with malnutrition he doesn 't know how to cure it
and he 's operating in a hostileenvironment and people do terrible things in wars the german camp guards they 've got bored they 've taken to just firing into the prison camp at random for fun
on one particular occasion one of the guards threw a grenade into the prisoners lavatory while it was full of prisoners he said he heard suspicious laughter
and archie cochrane as the camp doctor was one of the first men in to clear up the mess
he 'd already smuggled vitamin c into the camp and now he managed to get hold of supplies of marmite on the black market now some of you will be wondering what marmite is
so archie splits the men under his care as best he can into two equal groups he gives half of them vitamin c he gives half of them vitamin b twelve he very carefully and meticulously notes his results in an exercise book
marmite is the cure so cochrane then goes to the germans who are running the prison camp
and then he goes back to his quarters
breaks down and weeps because he 's convinced that the situation is hopeless but a young german doctor
picks up archie cochrane 's exercise book
and says to his colleagues this evidence is incontrovertible if we don 't supply vitamins to the prisoners
now i 'm not telling you this story because i think archie cochrane is a dude although
archie cochrane is a dude i 'm not even telling you the story because i think we should be running more carefully controlled randomized trials in all aspects of public policy although i think that would also be completely awesome i 'm telling you this story because archie cochrane all his life
and he realized it was debilitating to individuals and it was corrosive to societies and he had a name for it he called it the god complex
now i can describe the symptoms of the god complex very very easily so the symptoms of the complex are no matter how complicated the problem you have an absolutelyoverwhelmingbelief that you are infallibly right in your solution
now archie was a doctor
so he hung around with doctors a lot and doctors suffer from the god complex a lot now i 'm an economist i 'm not a doctor but i see the god complex around me all the time in my fellow economists i see it in our business leaders i see it in the politicians we vote for
people who in the face of an incrediblycomplicated world are neverthelessabsolutely convinced that they understand the way that the world works
and you know with the future billions that we 've been hearing about the world is simply far too complex to understand in that way
imagine for a moment that instead of tim harford in front of you there was hans rosling presenting his graphs you know hans the mick jagger of ted
so it 'll show you gdp per capita population
longevity that 's about it so three pieces of data for each country three pieces of data three pieces of data is nothing
and he 's used techniques of networkanalysis to
interrogate this database and to graph relationships between the different products and it 's wonderful wonderful work you show all these interconnections all these interrelations
and i think it 'll be profoundly useful in understanding how it is that economies grow brilliant work cesar and i tried to write a piece for the new york times magazine explaining how this works and what we learned is cesar 's work is far too good to explain in the new york times magazine
products that 's still nothing
there are one hundred thousand there it would take you all day now imagine trying to count every different specific product and service on sale in a major economy such as tokyo london or new york it 's even more difficult in edinburgh because you have to count all the whisky and the tartan
if you wanted to count every product and service on offer in new york
there are ten billion of them it would take you three hundred and seventeen years
this is how complex the economy we 've created is and i 'm just counting toasters here i 'm not trying to solve the middle east problem the complexity here is unbelievable and just a piece of context the societies in which our brains evolved had about three hundred products and services you could count them in five minutes
so this is the complexity of the world that surrounds us this perhaps is why we find the god complex so tempting we tend to retreat and say we can draw a picture we can post some graphs we get it we understand how this works
and we don 't we never do
but the way we solve them is with humility to abandon the god complex and to actually use a problem solving technique that works and we have a problem solving technique that works now you show me a successful complex system
and i will show you a system that has evolved through trial and error here 's an example
this baby was produced through trial and error i realize that 's an ambiguous statement maybe i should clarify it this baby is a human body it evolved what is evolution over millions of years variation and selectionvariation and selection
trial and error trial and error and it 's not just biological systems that produce miracles through trial and error you could use it in an industrial context so let 's say
then the spray dries it turns into powder it falls to the floor you scoop it up you put it in cardboard boxes you sell it at a supermarket you make lots of money
how do you design that nozzle
you find yourself a mathematician you find yourself a physicist somebody who understands the dynamics of this fluid and he will or she will calculate the optimal design of the nozzle now unilever did this
and it didn 't work too complicated even this problem too complicated but the geneticist professor steve jones describes how unilever actually did solve this problem
trial and error variation and selection
why it works no idea at all and the moment you step back from the god complex let 's just try to have a bunch of stuff let 's have a systematic way of determining what 's working and what 's not you can solve your problem
ten percent of american businesses disappear every year
that is a huge failure rate it 's far higher than the failure rate of say americans ten percent of americans don 't disappear every year which leads us to conclude american businesses fail faster than americans and therefore american businesses are evolving faster than americans
and eventually they 'll have evolved to such a high peak of perfection that they will make us all their pets
if of course they haven 't already done so i sometimes wonder
this incredibleperformance of western economies it didn 't come because you put some incredibly smart person in charge
it 's come through trial and error now i 've been sort of banging on about this for the last couple of months and people sometimes say to me well tim it 's kind of obviousobviously trial and error is very important obviously experimentation is very important now why are you just wandering around saying this obvious thing
i will admit it 's obvious when
schools start teaching children
that there are some problems that don 't have a correct answer stop giving them lists of questions every single one of which has an answer and there 's an authority figure in the corner behind the teacher 's desk who knows all the answers and if you can 't find the answers you must be lazy or stupid
when schools stop doing that all the time i will admit that yes it 's obvious that trial and error is a good thing when a politician stands up campaigning for elected office and says i want to fix our health system i want to fix our education system i have no idea how to do it
i have half a dozen ideas we 're going to test them out they 'll probably all fail then we 'll test some other ideas out we 'll find some that work we 'll build on those we 'll get rid of the ones that don 't when a politician campaigns on that platform and more importantly when voters like you and me are willing to vote for that kind of politician
then i will admit that it is obvious
the question of where is it that patients should recover from heart attacks should they recover in a specialized cardiac unit in hospital or should they recover at home
all the cardiac doctors tried to shut him down they had the god complex in spades they knew that their hospitals were the right place for patients and they knew it was very unethical to run any kind of trial or experiment
i swapped the two columns around it turns out your hospitals are killing people
and they should be at home would you like to close down the trial now
or should we wait until we have robust results
tumbleweed rolls through the meeting room
but cochrane would do that kind of thing
and the reason he would do that kind of thing is because he understood it feels so much better to stand there and say here in my own little world i am a god i understand everything i do not want to have my opinions challenged i do not want to have my conclusions tested
it feels so much more comfortable simply to lay down the law
cochrane understood that uncertainty that fallibility that being challenged they hurt and you sometimes need to be shocked out of that now i 'm not going to pretend that this is easy
it isn 't easy it 's incrediblypainful and since i started talking about this subject and researching this subject i 've been really haunted by something a japanese mathematician said on the subject
it turned out to be absolutelyinstrumental many decades later in proving fermat 's last theorem in fact it turns out it 's equivalent to proving fermat 's last theorem you prove one you prove the other
but it was always a conjecture
taniyama tried and tried and tried and he could never prove that it was true and shortly before his thirtieth birthday in one thousand nine hundred and fifty eight yutaka taniyama killed himself
his friend goro shimura who worked on the mathematics with him many decades later reflected on taniyama 's life
he said
he was not a very careful person as a mathematician
he made a lot of mistakes but he made mistakes in a good direction i tried to emulate him but i realized it is very difficult
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