I would like to know if the right to decide what is 'normal' and 'abnormal'

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I would like to know if the right to decide what is 'normal' and 'abnormal' belongs to any particular authority or type of expert. Whose job is it to define what is 'normal' and 'abnormal'? Is it the job of philosophers, or sociologists or another authority? Or a combination of these disciplines? Or is it not up to any type of authority and is instead up to everyday people with no particular expertise? Example: French historian and philosopher of history, Amaury de Riencourt claimed in one of his books that "Far from being an incomplete form of maleness...femaleness is the norm, the fundamental form of life." This statement implies that to be male is to be abnormal. Is he right because of his credentials? Are there counterarguments to this statement? If I disagreed with this statement, would I be wrong becuase I have no credentials to my name?