Harry Potter and the Half-Blood Prince Theme of Good vs. Evil

Sometimes it is easy and comforting to argue that there is a good side and an evil side in the world. It is easy to position Harry and Dumbledore as good, and to position Voldemort as evil. However, Harry Potter and the Half-Blood Prince complicates this clear-cut, black-and-white perception, focusing on the gray area in between. Here we learn how Voldemort came to have a desire to inflict evil deeds upon the world, and we are left to wonder what he might have done had he experienced more goodness in his life at a young age. We also see Harry accidentally play around with some Dark Magic. In Book 6 the issue of good and evil is far more complex than meets the eye.

1. Is there such a thing as "good" and such a thing as "evil" in this story?
2. What is an example of something or someone "good" in this story? An example of something or someone "evil" in this story?
3. Is Voldemort evil?
4. What makes someone "good," and what makes them "evil"?
5. How is evil defined in the world of this story?
6. Did your opinion of Harry change when he started playing around with the Half-Blood Prince's darker spells?