The Willow-Bark Fallacy

I’m reading Druin Burch’s Taking the Medicinefrom which I discovered the following anecdote and insight:

In 1757, an English clergyman named Edward Stone took a walk. For unknown reasons (even to Stone) he decided to taste the bark of a willow tree. It was bitter. But it reminded Stone of cinchona, which at the time was used to cure malaria. Stone subscribed to the ancient and erroneous maxim that “many natural maladies carry their cures along with them or that their remedies lie not far from their causes.” From this, he reasoned that “since malaria was very coming in the marshy places where willow grew” Burch writes, “it was likely that the tree would cure the disease.”

Stone collected the bark, waited a few months until it was dry and pounded it into a powder. He began treating patients who had malaria and discovered that the bark was an efficacious treatment. Given that cinchona was expensive (it had to be shipped from South American) this was good news. Stone wrote a letter to the Royal Society and his remedy was adapted around the country.

The problem was the dried willow bark didn’t cure malaria – it simply reduced fevers (it was later synthesized and is now the main ingredient in aspirin). As Burch points it, “Stone’s achievement was to note a real effect of the bark – its ability to bring down fevers – even though he mistook this for a guarantee of its helping provide a cure.” It gets worse. When the Napoleonic war broke out, importing cinchona became harder, which rose the demand for the bark. “Willow, which did not cure malaria, thus partly replaced cinchona, which did.”

So let us term this The Willow Bark Fallacy: improving something based on erroneous beliefs and falsely believing that you know what you’ve improved, which actually renders things worse off in the long run.  

2 Responses to “The Willow-Bark Fallacy”

  1. EsLam

    I am so sorry for your loss. Even when you are expecting it, it is still hard. The first week is the hadsret in my experience. Just try to distract yourself and cry when you need to. Sam was an adorable and cheerful little dude and we all know that you gave him a good life. He was part of your family. My advice is to keep his things but put them out of sight for now. Create a memorial of some kind. My dog Agnes died in October and I still haven’t put together hers but I have photos and her collar to use. Best wishes for you in this difficult time.

  2. Anderson

    It’s very comforting to have some sort of small meamriol, at least for me. When our retriever died a few years ago, our vet was kind enough to make a mold of his paw print to send to us after some time had passed. It’s nice to have that on a shelf with his collar and ashes, and I made a photo book of our favorite pictures of him.