A Cat Is Witty, He Has Nerve,

Pure Logic Could Never Lead Us To Anything But Tautologies; It Can Create Nothing New; Not From It Alone Can Any Science Issue.

One Geometry Cannot Be More True Than Another; It Can Only Be More Convenient.

For A Long Time The Objects That Mathematicians Dealt With Were Mostly Ill-defined; One Believed One Knew Them, But One Represented Them With The Senses And Imagination; But One Had But A Rough Picture And Not A Precise Idea On Which Reasoning Could Take Hold.

If One Looks At The Different Problems Of The Integral Calculus Which Arise Naturally When One Wishes To Go Deep Into The Different Parts Of Physics, It Is Impossible Not To Be Struck By The Analogies Existing.

What Is A Good Definition? For The Philosopher Or The Scientist, It Is A Definition Which Applies To All The Objects To Be Defined, And Applies Only To Them; It Is That Which Satisfies The Rules Of Logic. But In Education It Is Not That; It Is One That Can Be Understood By The Pupils.