"Observation is not passive. It is an activity;" "the way we see things is a combination of what is there and of what we expected to find." "For the most part we do not first see, and then define, we define first and then see."

"Observation is a matter of training, it is a matter of recognizing what one is looking at." "The more untrained a mind, the more readily it works out a theory that two things which catch its attention at the same time are causally connected ... we readily accept sequence or parallelism as equivalent to cause and effect." "The observer needs to be able reliably to recognize the facts being observed. If the observer is not reliable then neither will his reports be reliable."

"When men act on the principle of intelligence they go out to find the facts and to make their wisdom. When they ignore it, they go inside themselves and find only what is there." "Concepts which have proved useful for ordering things easily assume so great an authority over us, that we forget their terrestrial origin and accept them as unalterable facts." "The analysis is 'locked'; the range of judgment is confined within a context of facts which excludes judging the context in which the facts are made, man-made, and in which their meaning, function, and development are determined." "Customs, manners, and morality become established as the truth, or as what may be expected, and are then represented without question."

"It is therefore not just an idle game to exercise our ability to analyze familiar concepts, and to demonstrate the conditions on which this justification of their usefulness depend."