Whether We Electrons, Light Quanta, Benzol Molecules,

It Was About Three O'clock At Night When The Final Result Of The Calculation [which Gave Birth To Quantum Mechanics] Lay Before Me ... At First I Was Deeply Shaken ... I Was So Excited That I Could Not Think Of Sleep. So I Left The House ... And Awaited The Sunrise On Top Of A Rock.

The Very Act Of Observing Disturbs The System.

You May Object That By Speaking Of Simplicity And Beauty I Am Introducing Aesthetic Criteria Of Truth, And I Frankly Admit That I Am Strongly Attracted By The Simplicity And Beauty Of Mathematical Schemes Which Nature Presents Us. You Must Have Felt This Too: The Almost Frightening Simplicity And Wholeness Of The Relationship, Which Nature Suddenly Spreads Out Before Us.

Can Quantum Mechanics Represent The Fact That An Electron Finds Itself Approximately In A Given Place And That It Moves Approximately With A Given Velocity, And Can We Make These Approximations So Close That They Do Not Cause Experimental Difficulties?

The More Precise The Measurement Of Position, The More Imprecise The Measurement Of Momentum, And Vice Versa.