The other night a barmaid informed me that if you pour beer into a damp glass it goes flat much more quickly. She added that to dip your moustache into your beer also turns it flat. I immediately accepted this without further inquiry; in fact, as soon as I got home I clipped my moustache, which I had forgotten to do for some days.
Only later did it strike me that this was probably one of those superstitions which are able to keep alive because they have the air of being scientific truths. In my note-book I have a long list of fallacies which were taught to me in my childhood, in each case not as an old wives’ tale but as a scientific fact. I can’t give the whole list, but there are a few hardy favourites:
That a swan can break your leg with a blow of its wing.
That if you cut yourself between the thumb and forefinger you get lockjaw.
That powdered glass is poisonous.
That if you wash your hands in the water eggs have been boiled in (why anyone should do this is a mystery) you will get warts.
That bulls become infuriated at the sight of red.
That sulphur in a dog’s drinking water acts as a tonic.
And so on and so forth. Almost everyone carries some or other of these beliefs into adult life. I have met someone of over thirty who still retained the second of the beliefs I have listed above. As for the third, it is so widespread that in India, for instance, people are constantly trying to poison one another with powdered glass, with disappointing results.
George Orwell, As I Please, 1944
Kingsley Amis reports that his landlady came into his room to collect his breakfast tray, and started closing the curtains. What are you doing, he asked. The sunlight puts the fire out, she responded. He explained that when the sunlight hit the fire, you could no longer see the flames, and it looked as if it was going out. Oh really? And she closed the curtain.
The full set is here, in my book What You Know that Ain't So.
More here, and links to the rest.

