By Getting To Smaller And Smaller Units,

Both Matter And Radiation Possess A Remarkable Duality Of Character, As They Sometimes Exhibit The Properties Of Waves, At Other Times Those Of Particles. Now It Is Obvious That A Thing Cannot Be A Form Of Wave Motion And Composed Of Particles At The Same Time - The Two Concepts Are Too Different

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 Problems Of Language Here Are Really Serious. We Wish To Speak In Some Way About The Structure Of The Atoms. But We Cannot Speak About Atoms In Ordinary Language.

I Believe That The Existence Of The Classical "path" Can Be Pregnantly Formulated As Follows: The "path" Comes Into Existence Only When We Observe It.

An Expert Is Someone Who Knows Some Of The Worst Mistakes That Can Be Made In His Subject And How To Avoid Them.