A Clockwork Orange highlights the question of whether people are destined to their fate, or whether free will and external circumstances can influence people's life outcomes. Alex believes that humans are born evil and need cultivation to avoid evil. F. Alexander believes that humans are born good, but are corrupted by society and culture. The Government believes that the stability of the State trumps the happiness of its citizens, and readily abolishes moral choice (a fundamental human trait) in the name of stability. In contrast to this, Alex fights vehemently against the notion that his freedom to choose should be compromised at all, as free will is what makes him human to begin with.
A central part of being human is free will, the ability to choose among different options. While Alex has freedom of choice, he is as human as possible. When Alex is rendered unable to choose violence, thanks to Ludovico's Technique, Burgess sends the message that he no longer is human, but a mere clockwork orange.
People are born innocent, only to be corrupted by society and its ills. Societal corruption, though, is neither necessary nor irreversible. Alex, the protagonist-narrator of A Clockwork Orange, is the perfect case in point.