King Canute and False Etymologies

Many of us have received an e-mail with a subject such as “Who says history is boring!” that starts out something like this:

“The expression ‘rule of thumb’ comes from the Medieval English law that a man was not allowed to beat his wife with a stick thicker than his thumb.”

The message goes on to give a list of “etymologies” of a number of other words and expressions. All of them are complete fabrications. Most of them are ridiculous.

Why would someone compose such a list? I can think of only three reasons:

1. The author composed it as a joke, assuming no one would take it seriously. If this is the explanation, it involved a serious overestimation of most people’s knowledge of etymology (or of most people’s intelligence).

2. The author simply invented it all, assuming that any plausible-sounding expanation he or she could think up would somehow automatically be true.

3. The author wrote it maliciously, in an effort to spread wrong information. Why? To see how far it would spread? To see whether people would believe it? To speed the dumbing-down of the general population and the decline of Western civilization in general?

Whatever the true reason, the thing has now taken on a life of its own and continues to make the rounds of e-mail In Boxes, possibly achieving the last-listed goal of putative author number 3.

Knowing that the attempt is probably futile, I am nonetheless going to attempt to correct some of this nonsense.


First of all, the expression is “rule of thumb,” not “law of thumb.”

There has never been been a law specifically permitting men to beat their wives. (Either it went without saying, or it was forbidden under the general laws concerning assault and battery.)

“Rule” is in this instance is used in an archaic sense, as a synonym of “ruler.”

THE TRUTH: The expression refers to the practice of using the first joint of one’s thumb, which is about an inch long, as a handy substitute for a measuring stick. “By rule of thumb” is therefore used metaphorically to mean “using a rough method of approximation.”1


The false etymologist would have us believe that this stems from the medieval pubkeeper’s admonition to his serving wenches and means, “Don’t get pints and quarts mixed up.” It’s not true.

Beer and ale are served in pints and half-pints, not pints and quarts.

Not even a blind serving wench could ever mistake a pint for a quart.

Nobody has ever referred to pints and quarts as p’s and q’s.

THE TRUTH: The expression comes from typesetting: in the early days, the compositor actually picked individual letters out of the type case one at a time to set text. Lowercase p and q are mirror images, otherwise identical, which makes them hard to distinguish from each other. “Mind your p’s and q’s” was thus a warning given to apprentice compositors handling or setting type.


The creative etymologist explains that in the winter, puppies and kittens climbed (how?) up into the roof thatch to keep warm (instead of sitting by the fire?). When it rained, they fell out, sometimes because “wet thatch is slippery,” sometimes because of the wind—whatever creative explanation our author was able to come up with.

Does anyone really believe this?

THE TRUTH: Unfortunately the truth is more complicated and less colorful. “In northern mythology the CAT is supposed to have great influence on the weather….The DOG is a signal of wind, like the WOLF, both of which were attendants of ODIN, the storm god. Thus cat may be taken as a symbol of the down-pouring rain, and dog of the strong gusts of wind accompanying a rainstorm.”1


Supposedly people got married in June because they only bathed once a year, in May, and weren’t too stinky yet in June. The bride carried a bouquet to further mask any smell of sweat.

THE TRUTH: June has been considered a lucky month for weddings since Roman times, when rich people bathed quite a lot: June is named for Juno, the guardian of women from birth to death. The bouquet is “a relic of the corona nuptialis used by the Greeks and Romans to indicate triumph.”1


Our creative etymologist really goes to town with this one, telling a long story with some creative reason why “thresh,” helpfully defined as “straw,” was strewn on the floor, and how this, when piled high, would slip out the door, necessitating a piece of wood in the entrance to hold it in.

“To thresh” is a verb meaning to separate the grain from the stalk. There is no noun “thresh.”

People who spread straw (or rushes, or sand) on their floors had to be able to sweep the dirty material out the door when it needed to be replaced. They were therefore precisely the ones who would not want a threshold.

How high would you have to pile the straw before it started slipping out the door? Would you even be able to walk through straw piled that high?

THE TRUTH: “threshold” comes from Old Norse threskjöldr, meaning “threshold.”2 Sometimes, despite how they sound or look, words mean just, and only, what they mean: “missile” does not have anything to do with missing an ile, and “threshold” does not have anything to do with holding a thresh.


These have nothing to do with the notion that so many people were buried alive that bells, or strings attached to bells, were put into the coffin with the corpse, in case it turned out not to be a corpse; or with the resultant idea that someone had to sit in the graveyard and listen for the ringing of the bell.

(In any case, a person who was actually dead wouldn’t ring the bell, and a person who rang the bell wouldn’t be dead; thus neither could properly be called a “dead ringer.”)

THE TRUTH: both of these expressions are in fact American and thus do not date back to the Middle Ages. A “ringer” is “someone who enters a competition under false pretenses,”2 and “dead” in this expression is used in the sense of “exact,” as in “dead center” or “dead reckoning.” So a very fast horse that exactly resembled a slower horse might be fraudulently entered in a race under the name of the slower horse, in order to improve the odds.

And, “in World War II the name given by shift workers in munitions factories, etc., to the shift covering the midnight hours” was “graveyard shift.”1

(For an explanation of  King Canute and why I invoked his name in the title of this essay, please see this blog post.)

1 Brewer’s Dictionary of Phrase & Fable, Ivor H. Evans, ed. Harper & Row. Centenary edition, revised, 1981. (It is actually possible to look these things up.)

2 Webster’s Third New International Dictionary.