Hoisted By My Own Petard

I received the following email from someone who calls himself my friend:

One of the gimmicks I detest most is the “$99 value, yours for only $24.99,”…

vs.

Men, Women, and Girl Singers
Retail Price: $14.95
Online Sale Price: $13.46

That’s all it said, and the subject line was “LOL”

It had me scratching my head for a minute or three. The detested gimmick part came from my post on Friday, but $13.46? Where did that come from? I sell a few copies of my own book from time to time, but I don’t sell at a discount. I called my friend. “Where’d you find that?” I asked. Now he really was laughing out loud. “You posted the link on your site.”

DUH.

After kicking myself three times and wishing for home, I tried to wiggle out of culpability – after all, I didn’t come up with the price; that was my friends at ejazzlines.

“You cash the checks?” he asked.

Hoisted by my own petard.

It’s a clichéd phrase, and we know what it means, but do we really use the expression correctly? And what, exactly, is a petard?

The word: I have always assumed that a petard was a rope. I fantasized that it was a nautical term, imagining a hanging by pirates at sea — I don’t know where I got that idea. I thought that to be hoisted by ones own petard was akin to being given enough rope to hang oneself. But a petard is not a rope, it’s a bomb. My Visual Thesaurus by ThinkMap says that a petard is an explosive device from Medieval days (sometime between 300 and 1500 AD) used to break down as gate or wall. My Oxford English Dictionary on CD-ROM is more specific, defining it as “A small bomb made of a metal or wooden box filled with powder, used to blow in a door etc. or to make a hole in a wall,” and citing first use as mid sixteenth century (specifically between 1530 and 1569). The derivation? Péter meaning “break wind.”

The expression: “Hoist with one’s own petard” was coined by Shakespeare in Hamlet (sometime between 1600 and 1602) A Wikipedia entry explains

The phrase is usually misquoted as “see the engineer hoist by his own petard” and is taken to mean “the hangman hanged with his own rope,”… Hamlet’s actual meaning is “cause the bomb maker to be blown into the air with his own bomb,” metaphorically turning the tables on Claudius, whose messengers are killed instead of Hamlet.

Wikipedia also asserts that “a petard was a 19th Century animal trap, consisting of a rope and a bent branch that caught the desired beast by one leg as it stepped into a loop in the rope and pulled it up into the air.” However, I can not find any corroboration for this other than some online chatter that seems to have proliferated the aforementioned definition intact. There is no such mention in any of my reference books.

In any case, the gist is being ruined by one’s own devices, whatever that device may be…bomb, rope, or poison pen.