From Wikipedia
Teaching grandmother to suck eggs is an English saying meaning that a person is giving advice to someone else about a subject that they already know about - and probably more than the first person. "Egg sucking" removed the egg contents while preserving the shell intact. Two small holes were made on the ends of the egg, and the contents sucked out. The shell could then be painted (Ukrainian Easter egg) or otherwise used for decorative purposes without it becoming rotten and smelling bad.
Origins of the phrase
The origins of the phrase are not clear. The Old English Dictionary and others suggest that it comes from a translation in 1707, by J. Stevens, of Francisco de Quevedo, a Spanish author: "You would have me teach my Grandame to suck eggs."
Recorded usage
- Its use was recorded in Tom Jones by Henry Fielding, published in 1749:
“I remember my old schoolmaster, who was a prodigious great scholar, used often to say, Polly matete cry town is my daskalon. The English of which, he told us, was, That a child may sometimes teach his grandmother to suck eggs”
- Letter from Percy Bysshe Shelley to Leigh Hunt, 8/15/1819:
“But what am I about? If my grandmother sucks eggs, was it I who taught her?”
- The phrase was used in the 1890s in a Punch magazine cartoon:
"You see, Grandmama, before you extract the contents of this bird's egg by suction, you must make an incision at one extremity, and a corresponding orifice at the other." Grandmama's response is to the effect, "Dearie me! And we used to just make a hole at each end."
- In "Hog on Ice" (Harper & Row, New York, 1948), Charles Earle Funk says:
"To teach one's grandmother to suck eggs - To offer needless assistance; to waste one's efforts upon futile matters; especially, to offer advice to an expert. This particular expression is well over two hundred years old; it is just a variation of an older theme that was absurd enough to appeal to the popular fancy.
- The phrase has been used in the movie The Big Country:
"Go teach your grandmother to suck eggs! I've been handling guns like this, flintlock and caplock, since before you were born."
- The line was also used (as a reference to Burl Ives' character in The Big Country) in the sixth episode of the first season of The Ren & Stimpy Show:
"I don't think you're happy enough! That's right! I'll teach you to be happy! I'll teach your grandmother to suck eggs! Now, boys and girls, let's try it again!"
- The phrase has been paraphrased by the character Minsc in the role-playing video game Baldur's Gate. Referring to his genius "miniature-giant-space-hamster" Boo, he says:
"Don't teach my hamster to suck eggs!"
- Sméagol instructed his grandmother, as related in the Riddle Contest in Chapter Five of The Hobbit:
"But suddenly Gollum remembered thieving from nests long ago, and sitting under the river bank teaching his grandmother, teaching his grandmother to suck — ‘Eggses!’ he hissed.