If You Think You Understand Quantum Mechanics,

'conservation' (the Conservation Law) Means This ... That There Is A Number, Which You Can Calculate, At One Moment-and As Nature Undergoes Its Multitude Of Changes, This Number Doesn't Change. That Is, If You Calculate Again, This Quantity, It'll Be The Same As It Was Before. An Example Is The Conservation Of Energy: There's A Quantity That You Can Calculate According To A Certain Rule, And It Comes Out The Same Answer After, No Matter What Happens, Happens.

It Does Not Make Any Difference How Beautiful Your Guess Is. It Does Not Make Any Difference How Smart You Are, Who Made The Guess, Or What His Name Is If It Disagrees With Experiment It Is Wrong. That Is All There Is To It.

If An Apple Was Magnified To The Size Of The Earth, Then The Atoms In The Apple Would Be Approximately The Size Of The Original Apple.

John Von Neumann Gave Me An Interesting Idea: That You Don't Have To Be Responsible For The World That You're In. So I Have Developed A Very Powerful Sense Of Social Irresponsibility As A Result Of Von Neumann's Advice. It's Made Me A Very Happy Man Ever Since. But It Was Von Neumann Who Put The Seed In That Grew Into My Active Irresponsibility!

When A Scientist Doesn't Know The Answer To A Problem, He Is Ignorant. When He Has A Hunch As To What The Result Is, He Is Uncertain. And When He Is Pretty Darn Sure Of What The Result Is Going To Be, He Is In Some Doubt.