Many things on the Discworld are so patently obvious and self-evident that they come under the heading of Well-Known Facts, which are usually emphatically presented in spoken discourse and dogmatically topped off with a statement along the lines of "That's a Well-Known Fact, that is!"
A well-known proponent of using Well-Known Facts is Fred Colon, a man who had been to the School of My Dad Always Said, the College of It Stands to Reason, and is now a post-graduate student at the University of What Some Bloke In the Pub Told Me, and is thus extremely well-educated.
Most people are susceptible to using these Well-Known Facts in dire situations, as demonstrated by Susan Sto Helit's use of them to overcome certain difficulties with nougat.
A Well-Known Fact may also make serfect pense after a few tinnies of Roo Beer.
Well-Known Facts include such axioms as:-
- A Million-to-one chance comes up nine times out of ten.
- A chocolate you do not want to eat does not count as chocolate; and indeed, like food consumed whilst walking, contains no calories.
- Everybody knows the thing about Dwarfs - (Dwarfs are naturally well-endowed);
- Things that try to look like things often do look more like things than things;
- The pen is mightier than the sword (but only if it's a very small sword and it's a large well-sharpened pen);
- The more geography you've got, the less history you have;
- When you've got enemies at large, you do not get into the first cab that obligingly presents itself;
- Everyone knows that at the end of the week, you've never got quite as much money left as you think you should;
- Women should never be taught to read or write, nor indeed to attempt anything overly intellectual, as the effort involved, on a brain quite unsuited for it, will cause it to overheat and explode. A Well-Known Fact to a certain minority of the other half of the human (or Nomish) race...
- Hedgehogs do it very carefully, and indeed the prospect of sodomy is not one which exercises the spiny erinaceid mind very much. Well-known fact, and song.
- Where you get personality, you get irregularities. (This is stipulated even by the Auditors of Reality, who know their facts.)
- All anyone gets in a mirror is themselves, but what you gets in a good gumbo is everything.
- In times of trouble, the best thing to do is panic.