Given the way Bradbury constructs the world in which Montag lives, individual power is not always evident. It is a world that seeks to remove the voice of the individual and ensure that the "danger" of thought is removed.
However, as the story progresses, it becomes clear that individuals do possess power. Clarisse asking Montag whether he is happy displays power, as does Montag's rebellion. Individuals can display power, even in the most dehumanizing of circumstances.
The narrative presents the need for individuals to display power. Montag's words are proven to be true: There is a "a time to keep silence and a time to speak." Bradbury's conclusion speaks to how individuals can always find "the time to speak" even in the most challenging of conditions.