When you are having an argument and you see your logic begin to fail, you can use this phrase to automatically win. This of course only works if the reference is understood.

The phrase originates from a conversation that occured directly after a speech which described how the earth revolves around the sun.

At the end of the speech an elderly lady stood up and said,

"What you have told us is rubbish. The world is really a flat plate supported on the back of a giant tortoise."

The scientist then smugly asked,

"What is the tortoise standing on?"

"You're very clever, young man, very clever", said the old lady. "But it's turtles all the way down!"

This anecdote was made "popular" by Stephen Hawking, who told it at the begining of his book "A Brief History of Time."
"Your an idiot.. Theres 35 letters in the english alphabet not 26...

Lets count.

A = 1
B = 2
C = 3 "

....

"Z=26 ... ... um ...

then its just turtles all the way down. "
by Frggr February 13, 2010
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This is a traditional Scottish saying in rural Stirlingshire which means as it sounds in English 'May your turtles have 3 heads'. It is a phrase typically used by those who aim to wish a person a deep sleep. It is unclear of the origins of the phrase, especially as there are no wild turtles in Scotland and Stirlingshire has no coast, however it may have originated when Scotland was a driving force of the commonwealth.
"I'm aff tae bed now, cheery ho"
"Aright then, May all yer turles hae' three heids"
"Thanks pal, and yae tae"

May all yer turtles hae' three heids
by Ayeknowaboutscotland July 26, 2014
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