In 1847, a young Hungarian physician called Ignac Semmelweis made a groundbreaking discovery that was to save thousands of lives.
By getting maternity ward doctors to wash their hands regularly, he cut the mortality rate of mothers from 18% to 1%. Yet the medical profession met his handwashing regime with scorn and ridicule.
The phrase 'Semmelweis Effect' was coined to describe this common reflex-like rejection of new ideas. It happens in business, too - bosses, like doctors, often think they know best. Take the example of inventor James Dyson and his bagless vacuum cleaner. So uninterested were the established players in accepting his big idea that Dyson had to make it himself. And the naysayers missed a trick: Dyson's company now sells four times as many vacuums in the UK as its nearest rival.
So why are some experts - medics and businesspeople among them - so reluctant to accept the benefits of innovation? Often, it's because, having become successful themselves, they start to see success as their right, rather than a privilege earned continuously through hard work and fresh thinking. The way to prove them wrong is to do a Dyson.
But although this is bad news for patients and big business, entrepreneurs appreciate the Semmelweiss Effect, as many of their businesses might never have got off the ground without it.
Jennifer Harris is director of JRBH Strategy & Management, www.jrbh.co.uk