All This, The Positive And Physical Essence

Not Bodies Produce Sensations, But Element-complexes (sensation-complexes) Constitute The Bodies. When The Physicist Considers The Bodies As The Permanent Reality, The 'elements' As The Transient Appearance, He Does Not Realise That All 'bodies' Are Only Mental Symbols For Element-complexes (sensation-complexes).

What Mach Calls A Thought Experiment Is Of Course Not An Experiment At All. At Bottom It Is A Grammatical Investigation.

I Know Of Nothing More Terrible Than The Poor Creatures Who Have Learned Too Much. Instead Of The Sound Powerful Judgement Which Would Probably Have Grown Up If They Had Learned Nothing, Their Thoughts Creep Timidly And Hypnotically After Words, Principles And Formulae, Constantly By The Same Paths. What They Have Acquired Is A Spider's Web Of Thoughts Too Weak To Furnish Sure Supports, But Complicated Enough To Provide Confusion.

Science Itself, Therefore, May Be Regarded As A Minimal Problem, Consisting Of The Completest Possible Presentment Of Facts With The Least Possible Expenditure Of Thought.

Everyone Is Free To Set Up An Opinion And To Adduce Proofs In Support Of It. Whether, Though, A Scientist Shall Find It Worth His While To Enter Into Serious Investigations Of Opinions So Advanced Is A Question Which His Reason And Instinct Alone Can Decide. If These Things, In The End, Should Turn Out To Be True, I Shall Not Be Ashamed Of Being The Last To Believe Them.