Originally Posted by
jackofwind
You keep mentioning someone bullying him, but that's a really single-minded way of looking at tragic characters. I already mentioned Macbeth in this thread as a strong example of a character who has a tragic story yet also becomes a villain whose actions are totally unjustifiable. I don't disagree with your description of The Joker at all, but that description doesn't preclude him from being a tragic character unless he was born that way.
A tragic character is just one who has a fall from status and ends up being villainous. It doesn't mean they have to be a bullied kid, nor that they are out seeking revenge. They can be driven by basically anything, including their own unhinged mental machinations.