Just As Houses Are Made Of Stones,

Einstein Does Not Remain Attached To The Classical Principles, And When Presented With A Problem In Physics He Quickly Envisages All Of Its Possibilities. This Leads Immediately In His Mind To The Prediction Of New Phenomena Which May One Day Be Verified By Experiment.

I Then Began To Study Arithmetical Questions Without Any Great Apparent Result, And Without Suspecting That They Could Have The Least Connexion With My Previous Researches. Disgusted At My Want Of Success, I Went Away To Spend A Few Days At The Seaside, And Thought Of Entirely Different Things. One Day, As I Was Walking On The Cliff, The Idea Came To Me, Again With The Same Characteristics Of Conciseness, Suddenness, And Immediate Certainty, That Arithmetical Transformations Of Indefinite Ternary Quadratic Forms Are Identical With Those Of Non-euclidian Geometry.

Geometry Is Not True, It Is Advantageous.

All Of Mathematics Is A Tale About Groups.

If We Ought Not To Fear Mortal Truth, Still Less Should We Dread Scientific Truth. In The First Place It Can Not Conflict With Ethics? But If Science Is Feared, It Is Above All Because It Can Give No Happiness? Man, Then, Can Not Be Happy Through Science But Today He Can Much Less Be Happy Without It.