Analogize physics to language. Language and its lexicon are ways of encoding ideas about phenomena, concepts and their relationships to each other. Physics is a way of encoding ideas about phenomena, concepts and their relationships to each other, often using mathematics. If in the extreme case the lexicon of a language changed each day communication would become impossible; people would have to spend all their time every day learning the new words. If in the opposite extreme case the lexicon never changed, it would limit the ability of society to improve understanding of phenomena and relationships between them, and to increase efficiency of artifacts including concepts and theories created by society. Over much change results in insufficient stability (too much chaos) to permit study of the natural world; over much stasis inhibits progress. Scientists as users of language have been implicitly convinced that language must have stability to be useful. Therefore physicists may resist over much change as creating too much instability to organize ideas while recognizing the need for change to adapt to growth in knowledge. Apart from the contest between stability and stasis which is a consideration in lexicons, in physics there is the additional consideration that a new idea should be theoretically and experimentally supportable and should be a sufficient improvement to existing concepts to warrant the collective energy required to learn, teach and incorporate it into the collective store of physics knowledge. Incidentally, I found that a similar question was posed on the website Quora, with interesting answers: www.quora.com/Why-do-scientists-resist-new-theories. What are your views?