Our species uses music and dance to express various feelings: love, joy, comfort, ceremony, knowledge, and friendship. And each one is distinct and widely recognized within cultures. Love songs cause us to move slowly and fluidly, for example, while songs of joy inspire us to dance in a full-body aerobic way.
The Potter books in general are a prolonged argument for tolerance, a prolonged plea for an end to bigotry. And I think it's one of the reasons that some people don't like the books, but I think that's it's a very healthy message to pass on to younger people that you should question authority and you should not assume that the establishment or the press tells you all of the truth.
The humans live in time but our Enemy destines them to eternity. He therefore, I believe, wants them to attend chiefly to two things, to eternity itself, and to that point of time which they call the Present. For the Present is the point at which time touches eternity. Of the present moment, and of it only, humans have an experience analogous to the experience which our Enemy has of reality of whole; in it alone freedom and actuality are offered to them.