Context

This quote is from Greek mathematician and inventor Archimedes regarding the Law of the Lever at some point during his life (born 287 BCE).

Archimedes explained the simple machines of physics, like the pulley, the fulcrum, and—for the rest of us—the calculator. (Okay, that one would come a few years later.)

One of his most famous quotes is regarding the lever, in which he said, depending on your translation, "Give me but one firm spot on which to stand and I will move the earth."

Where you've heard it

Archimedes is best known as the naked "Eureka!" guy. What soap did Archimedes use in the bath? Lever 2000.

Fun fact: Some mathematicians figured out exactly how long a lever a person would need to move the Earth. In layman's terms: a really long one. 

Pretentious Factor

If you were to drop this quote at a dinner party, would you get an in-unison "awww" or would everyone roll their eyes and never invite you back? Here it is, on a scale of 1-10.

If Archimedes moved the Earth with a lever, it would barrel straight into Venus. And he didn't. So no one can do it.