What A Man Sees Depends

Groups Do Not Have Experiences Except Insofar As All Their Members Do. And There Are No Experiences... That All The Members Of A Scientific Community Must Share In The Course Of A [scientific] Revolution. Revolutions Should Be Described Not In Terms Of Group Experience But In Terms Of The Varied Experiences Of Individual Group Members. Indeed, That Variety Itself Turns Out To Play An Essential Role In The Evolution Of Scientific Knowledge.

The Resolution Of Revolutions Is Selection By Conflict Within The Scientific Community Of The Fittest Way To Practice Future Science. The Net Result Of A Sequence Of Such Revolutionary Selections, Separated By Periods Of Normal Research, Is The Wonderfully Adapted Set Of Instruments We Call Modern Scientific Knowledge.

Individuals Who Break Through By Inventing A New Paradigm Are Almost Always Either Very Young Men Or Very New To The Field Whose Paradigm They Change. These Are The Men Who, Being Little Committed By Prior Practice To The Traditional Rules Of Normal Science, Are Particularly Likely To See That Those Rules No Longer Define A Playable Game And Conceive Another Set That Can Replace Them.

As In Political Revolutions, So In Paradigm Choice-there Is No Standard Higher Than The Assent Of The Relevant Community... This Issue Of Paradigm Choice Can Never Be Unequivocally Settled By Logic And Experiment Alone.

The Answers You Get Depend Upon The Questions You Ask.