List of Henri Poincare Quotes

When The Logician Has Resolved Each Demonstration Into A Host Of Elementary Operations, All Of Them Correct, He Will Not Yet Be In Possession Of The Whole Reality, That Indefinable Something That Constitutes The Unity ... Now Pure Logic Cannot Give Us This View Of The Whole; It Is To Intuition That We Must Look For It.

Later Generations Will Regard Mengenlehre (set Theory) As A Disease From Which One Has Recovered.

This Harmony That Human Intelligence Believes It Discovers In Nature - Does It Exist Apart From That Intelligence? No, Without Doubt, A Reality Completely Independent Of The Spirit Which Conceives It, Sees It Or Feels It, Is An Impossibility. A World So Exterior As That, Even If It Existed, Would Be Forever Inaccessible To Us. But What We Call Objective Reality Is, In The Last Analysis, That Which Is Common To Several Thinking Beings, And Could Be Common To All; This Common Part, We Will See, Can Be Nothing But The Harmony Expressed By Mathematical Laws.

Need We Add That Mathematicians Themselves Are Not Infallible?

It Is A Misfortune For A Science To Be Born Too Late When The Means Of Observation Have Become Too Perfect. That Is What Is Happening At This Moment With Respect To Physical Chemistry; The Founders Are Hampered In Their General Grasp By Third And Fourth Decimal Places.

A Very Small Cause, Which Escapes Us, Determines A Considerable Effect Which We Cannot Ignore, And We Say That This Effect Is Due To Chance.

But For Harmony Beautiful To Contemplate, Science Would Not Be Worth Following.

It Is The Simple Hypotheses Of Which One Must Be Most Wary; Because These Are The Ones That Have The Most Chances Of Passing Unnoticed.

Just As Houses Are Made Of Stones, So Is Science Made Of Facts.

Geometry Is Not True, It Is Advantageous.

Hypotheses Are What We Lack The Least.

Every Phenomenon, However Trifling It Be, Has A Cause, And A Mind Infinitely Powerful, And Infinitely Well-informed Concerning The Laws Of Nature Could Have Foreseen It From The Beginning Of The Ages. If A Being With Such A Mind Existed, We Could Play No Game Of Chance With Him; We Should Always Lose.