Personally, People Know Themselves Very Poorly.

The Plain Man Is Familiar With Blindness And Deafness, And Knows From His Everyday Experience That The Look Of Things Is Influenced By His Senses; But It Never Occurs To Him To Regard The Whole World As The Creation Of His Senses.

A Colour Is A Physical Object As Soon As We Consider Its Dependence, For Instance, Upon Its Luminous Source, Upon Other Colours, Upon Temperatures, Upon Spaces, And So Forth.

Bodies Do Not Produce Sensations, But Complexes Of Elements (complexes Of Sensations) Make Up Bodies.

To Us Investigators, The Concept 'soul' Is Irrelevant And A Matter For Laughter. But Matter Is An Abstraction Of Exactly The Same Kind, Just As Good And Just As Bad As It Is. We Know As Much About The Soul As We Do Of Matter.

The History Of The Development Of Mechanics Is Quite Indispensable To A Full Comprehension Of The Science In Its Present Condition. It Also Affords A Simple And Instructive Example Or The Processes By Which Natural Science Generally Is Developed.