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Pushkin. Hi,

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Tim Harford here with two pieces

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of news and a brand new

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mini cautionary tale for you. News

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headline number one. We're back in

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the studio recording a new Monster

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season of fourteen episodes

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of Cautionary Tales. There will

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be wonderful actors, hilarious calamities

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and tragic catastrophes Cautionary

0:43

Tales Season two. Stay

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tuned. News headline

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number two. I have a brand

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new book coming. If you're listening in

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the US or Canada, it's out early

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next year and it's called The Data

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Detective. It's never too early

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to pre order, so please consider doing

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that. But if you're listening anywhere

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else in the world, the book is out

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right now and it's called How

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to Make the World Add Up. On

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the surface, it's a book about statistics,

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but really it's a book about how to think

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clearly about the world. And

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if you want to know what the book is really about, gather

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close. I'm Tim

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Harford and this is

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a special mini episode of

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Cautionary Tales. You

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can make an estimate of how many children

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have been born into a Dutch or Danish

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family by counting the storks nests

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on the roof of their house. In statistical

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terminology, it would be said that a positive

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correlation has been found to exist between

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these two things. These

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are the words of Daryl Huff, the

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author of the most popular book about

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statistics ever written, How

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to Lie with Statistics. But

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of course, storks do not actually

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deliver baby is, no matter how

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strong the correlation may be. Half

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explains, big houses attract

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big and potentially big families, and

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big houses have more chimney pots on

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which storks may nest.

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Of course, sometimes

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it seems you can prove anything

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with statistics, especially

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things that aren't true. Darryl

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Huff's little book is a master class in

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skepticism. He exposes

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mistakes, half truths, and outright

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lies. Why, he explains,

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the crooks already know these tricks, honest

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men must learn them in self defense. Daryl

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Hulf made statistics seem like

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a game, or perhaps a stage

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magician's trick, all could

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fun, but never to be trusted. And

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I worry that we're starting to trust

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nobody. We're starting to believe

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that lying with statistics is all

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anyone ever does. But skepticism

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can easily curdle into cynicism,

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and cynicism can be corrosive

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after all. In nineteen fifty four, the

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very same year that Half published

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How To Lie With Statistics, two

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researchers, Richard Doll and

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Austin Bradford Hill, produced

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one of the first convincing demonstrations

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that smoking cigarettes caused

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lung cancer. They couldn't have figured

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that out without statistics. Even

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to notice the dramatic increase in lung

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cancer rates in the mid twentieth century

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required a statistical view of the

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world. So what

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Darrell Half saw as a trick, Richard

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Doll and Austin Bradford Hill saw

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as a tool, and a tool

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that has saved many millions

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of lives. Two

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visions of statistics had emerged

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at the same time, and they

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very quickly came into conflict, because

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as the evidence on smoking and

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cancer emerged, the tobacco

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companies fought back. When

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their product was so dangerous, so

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demonstrably dangerous, how

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on earth could they persuade people to

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keep smoking? In

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a stroke of twisted genius,

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they realized the answer scientific

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evidence was the enemy, so

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they had to give people reason to doubt

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that evidence without attacking

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it head on. They chose to

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emphasize uncertainty, the

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fact that experts disagree and

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to call for more research. Before anyone

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did anything hasty, they

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manufactured doubt,

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and it turns out that doubt is

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a really easy product to make. A

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couple of decades ago, two psychologists

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carry Edwards and Edward Smith, conducted

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an experiment to test how people

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felt about all sorts of politically

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fraught questions, including

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abortion rights, smacking children,

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and the death penalty for under sixteens.

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They invited people to produce as many

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arguments as they could in favor

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of or against the conclusion, given

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three minutes per topic. Of

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course, people found it easier to produce

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arguments that backed up what they already believed.

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Lots of researchers have found that, but

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more strikingly, Edwards and Smith found

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that disbelief seemed

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to flow more fluidly than belief.

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It's much easier to argue against

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positions you dislike than

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in favor of positions you support.

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Doubt has a special kind of

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power, and it is the easiest

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thing in the world to suggest that you

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should doubt what the statistics are telling

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you. This is why the simplest

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move in any argument today is

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to encourage people to believe

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nothing doubt

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is a powerful weapon. Now,

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statistics are a natural rural target,

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but honest statistics need to be defended

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because while it's easy to lie with

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statistics, it's even easier

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to lie without them. And there

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are plenty of things in this world, from

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the link between smoking and cancer to

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how to deal with the coronavirus epidemic,

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that we simply can't begin to understand

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without statistics. In a

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complex world, they are an

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essential tool. In

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the spring of nineteen sixty five, a

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US Senate committee was pondering

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the life or death matter of

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whether to put a health warning on packets

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of cigarettes. An

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expert witness appeared, and he

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wanted to throw doubt on the scientific

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evidence, so he

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turned to the topic of storks

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and babies. It turns out

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he said that households with more children

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also have more storks on their roofs.

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That old story about babies being

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delivered by storks was true,

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the expert went on, of course

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it wasn't. Correlation is

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not causation, and

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similarly, just because smoking

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was correlated with lung cancer didn't

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mean, not for a moment, that

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smoking caused cancer. Do

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you honestly think there is as casual

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a relationship between statistics linking

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smoking with disease as there is about

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storks, asked the committee

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chair. The expert witness

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replied that the two seemed

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to me the same. The

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witness's name was

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Darryl Huff. He had

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been paid by the tobacco lobby to do what he

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did best, weave together witty

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examples, some statistical savvy,

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and a certain amount of cynicism to

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cast doubt on the idea that cigarettes

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were dangerous. He was even working

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on a sequel to his masterpiece, although

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it was never published. The sequel's

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name was How to Lie

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with Smoking Statistics.

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I understand that statistics can seem

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intimidating, and they are often

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used deceitfully, but we mustn't

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give way to cynicism or

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feel helpless under the deluge of numbers.

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Understanding statistical claims doesn't

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require a deep technical background.

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If you're able to think, then you're able

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to think sensibly about

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statistical claims, which

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is why I've written a book about how to think

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more clearly about numbers and about

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the world. If you're listening in the US

8:44

or Canada, that book is called The Data

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Detective, and it's out early

8:49

next year, and if you're listening anywhere

8:51

else. The book is called How to Make

8:53

the World Add Up, and it's out

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now as a book, an e book, and as

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an audiobook read by me. If

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you like what I do here on Cautionary Tales,

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I really think you're going to love the book. The

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world is an amazing place, and

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these days, whatever you're interested in,

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the chances are you'll understand it much

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better through the lens of statistics.

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Don't be cynical, don't assume

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it's all a lie or a trick. Don't

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be afraid to pick up this statistical

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telescope and gaze around.

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This mini episode of Cautionary Tales

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was written and read by me Tim

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Harford. The producer was Ryan

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Dilley, and the music and sound design

9:42

by Pascal Wise. Cautionary

9:45

Tales is a Pushkin Industry's

9:47

production. I

10:10

don't don't be