Just As Houses Are Made Of Stones,

Les Faits Ne Parlent Pas. Facts Do Not Speak.

How Is It That There Are So Many Minds That Are Incapable Of Understanding Mathematics? ... The Skeleton Of Our Understanding, ... And Actually They Are The Majority. ... We Have Here A Problem That Is Not Easy Of Solution, But Yet Must Engage The Attention Of All Who Wish To Devote Themselves To Education.

In One Word, To Draw The Rule From Experience, One Must Generalize; This Is A Necessity That Imposes Itself On The Most Circumspect Observer.

Every Good Mathematician Should Also Be A Good Chess Player And Vice Versa.

Thought Is Only A Flash Between Two Long Nights, But This Flash Is Everything.