the book

Rating: 9/10 (21 November 2001)

With only the movie, the main theme may be deciphered, but it's stated more vaguely than in the book.
SPOILERS, interpretation:
"A Clockwork Orange" is the title of the book Home Guy was writing. Alex reads the first page before he rapes the guy's wife. The book is about the negative consequences of imposing human law and order onto the natural self. Alex later, in the book, spouts off a similar rant.
The movie and book are an argument for man's inherent evilness. It's an argument against the popular liberal enlightenment idea that man is born inherently good, and evil only later results as an effect of corrupt governments.
Alex no longer can commit evil in the end - though he can still will it - but he also has a breakdown and random hallucinations - he is not "cured" according to Burgess. According to Burgess, humans cannot be cured of evilness because it is a part of their authentic self. Rid yourself of evil, and rid yourself of yourself.
SPOILERS END, point of interest: I was quite surprised when I learned that the girl Billyboy and his gang almost raped and the two girls Alex has sex with were all only ten years old! - in the book that is. Also, the latter two girls are not as willing as the movie makes it seem. Really, Alex rapes them. He leaves them "bruised" and fighting him off with "punchipunchies."