Business is the only area of human activity where you get paid to change your mind

In 1891, a 29-year-old man moved from Philadelphia to Chicago intending to start a business. With $32 to his name, he began by selling scouring soap. Hoping to boost sales, he gave away small packets of baking powder with every purchase. Soon he found that the baking powder was more popular than his soap, so he quit the soap market and started selling baking powder instead.

But now he needed something to give away with his baking powder. Eventually, for reasons I cannot begin to fathom, he took to giving his customers two free packs of chewing gum with each tin of baking powder.

And then the same damned thing happened again. He found that the free gum was more popular than the baking powder. So he rolled up his sleeves and began anew, this time concentrating on the manufacture and sale of chewing gum. At this point business started to pick up. The young man’s name, by the way, was William Wrigley.

And herein lies one magic quality of business. It is the only area of human activity where you get paid to change your mind.

In politics, in punditry, in academia, there is great value attached to consistency. Changing your mind risks loss of face. Your ability to deliver plausible generalisations counts for a lot. There is social pressure to adopt the dominant frame of thought. No one gets invited on Newsnight to say ‘I’m not really sure’ and ‘It’s kind of complicated’.

Science claims to be self-correcting, of course. I don’t doubt that in some fields — pure mathematics, perhaps — it is. But a glance at the record suggests that reputational concerns —and deference to senior people in the field — make scientists remarkably slow to change their minds.