One of the great Ted Kennedy quotes:

[pnwmom]

I don't know if this was original to him, or just something he likes to say:

"Never let the perfect be the enemy of the good."

A message that we need to remind ourselves of over and over, I think. That motto of his is why he is one of the great achievers in the Senate. He -- though a progressive -- is willing to compromise in order to make progress. And he has always believed in reaching across the aisle.

[flowomo]

1. Voltaire: "Le mieux est l'ennemi du bien."

according to Wikiquote. "The best is the enemy of the good." The quote you cite is a variant and it and other variants are very common.

http://en.wikiquote.org/wiki/Voltaire