George Orwell's 1984 depicts a dystopian future society ruled by a totalitarian one-party state. Everything about Winston's daily life -- from his job, to the food he eats, even to what he watches on TV -- is tightly controlled and monitored by the state. Despite this invasive tyranny, Winston manages to think, to doubt, and finally, to risk autonomy.
Winston's character development demonstrates individualism because the character becomes progressively more autonomous and less restrained by the authoritarian system designed to govern his every action and thought. Moreover, his character demonstrates the inherent risk of individualism. The possibility of capture and torture are never far behind Winston; this danger is what makes his actions so meaningful and significant. Indeed, the latter half of the novel consists mainly of Winston fleeing the authorities who would have him detained and "re-educated."
Winston's character depicts individualism as a radical political act, the necessary antidote to totalitarian rule. Thus, the character helps us to understand what's at stake when we are confronted with a choice between individualism and agency on the one hand, and blind or fear-based obedience to authority on the other.