It Is With Logic That One Proves;

The Mind Uses Its Faculty For Creativity Only When Experience Forces It To Do So.

Geometry Is The Art Of Correct Reasoning From Incorrectly Drawn Figures.

Mathematicians Do Not Study Objects, But The Relations Between Objects.

Absolute Space, That Is To Say, The Mark To Which It Would Be Necessary To Refer The Earth To Know Whether It Really Moves, Has No Objective Existence.... The Two Propositions: "the Earth Turns Round" And "it Is More Convenient To Suppose The Earth Turns Round" Have The Same Meaning; There Is Nothing More In The One Than In The Other.

The Mathematical Facts Worthy Of Being Studied Are Those Which, By Their Analogy With Other Facts, Are Capable Of Leading Us To The Knowledge Of A Physical Law. They Reveal The Kinship Between Other Facts, Long Known, But Wrongly Believed To Be Strangers To One Another.