Jazz is about the only form of art existing today in which there is freedom of the individual without the loss of group contact.
Art may not have the power to change the course of history, but it can provide a perspective on historical events that needs to be heard, even if it's seldom heeded. After all the temporary influences that once directed the course of history have vanished, great art survives and continues to speak to each generation.
Duke Ellington, Art Tatum, and many other great jazz musicians objected to their music being called jazz. While the outside world may want to put a label on it, those who create it think of it just as music, and tend not to classify it.
