“In real life, I assure you, there is no such thing as algebra.”
– Fran Lebowitz
“As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.”
– Albert Einstein
“In mathematics you don’t understand things. You just get used to them.”
– Johann von Neumann
“We used to think that if we knew one, we knew two, because one and one are two. We are finding that we must learn a great deal more about ‘and’.”
– Sir Arthur Eddington
von Neumann is an old favourite of mine… :-)