1984 by George Orwell

Through its effective psychological manipulation tactics, the Party destroys all sense of independence and individuality. Everyone wears the same clothes, eats the same food, and lives in the same grungy apartments. Life is uniform and orderly. No one can stand out, and no one can be unique. To have an independent thought borders on the criminal. For this reason, writing such as Winston does in his diary has been outlawed. People are only permitted to think what the Party tells them to think, which leads to what Syme refers to as "duckspeak." Independent thought can be dangerous, as it might lead to rebellion.

This theme comes to a head during Winston's torture, when Winston argues that he is a man, and because he is a man O'Brien cannot tell him what he thinks. O'Brien counters that if Winston is a man, he is the last man on earth. Moreover, O'Brien suggests that this independence is evidence of insanity. O'Brien's view represents the purity of a totalitarian regime, in that independent thought must be destroyed to promote the needs and goals of the Party. Winston and Julia's downfall occurs because they believe they are special. Their arrest and torture, however, breaks this spirit. Once again, through this ultimate loss of individual thought, we witness Orwell's warning against embracing any version of totalitarian rule.

Ultimately the human spirit cannot overcome torture and terror.  This novel tells us that the spirit can be broken and can be controlled by others rather than by one's own striving.