Classes are back in session at our homeschool co-op, so I am again collecting short quotes for the blackboard. Here are the ones I used in September:
Any fool can know. The point is to understand.
Life without geometry is pointless.
You don’t understand anything until you learn it more than one way.
Denise Gaskins' Let's Play Math 
I think that is “Life without geometry…”
Of course, you are right! I guess I hadn’t had enough coffee when I was typing that…
Life without geometry is pointless.
Oh, that’s a real groaner. 😉