Who run the world? Witches.
When Luna was wise beyond her years.
From Order of the Phoenix.
When Hermione tried to convince Ron and Harry that the Half-Blood Prince could easily have been a girl.
From chapter 25 of Half Blood Prince.
When McGonagall told Umbridge like it is.
From chapter 29 of Order of the Phoenix.
When Hermione needed to sort out her priorities.
From Philosopher's Stone.