Strange As It May Sound, The Power

Thought Experiment Is In Any Case A Necessary Precondition For Physical Experiment. Every Experimenter And Inventor Must Have The Planned Arrangement In His Head Before Translating It Into Fact.

Similarly, Many A Young Man, Hearing For The First Time Of The Refraction Of Stellar Light, Has Thought That Doubt Was Cast On The Whole Of Astronomy, Whereas Nothing Is Required But An Easily Effected And Unimportant Correction To Put Everything Right Again.

Many An Article That I Myself Penned Twenty Years Ago Impresses Me Now As Something Quite Foreign To Myself.

The Fact Is, Every Thinker, Every Philosopher, The Moment He Is Forced To Abandon His One-sided Intellectual Occupation By Practical Necessity, Immediately Returns To The General Point Of View Of Mankind.

Mathematics May Be Defined As The Economy Of Counting. There Is No Problem In The Whole Of Mathematics Which Cannot Be Solved By Direct Counting.