The Underground Man is a spiteful man whose ideas we may agree with and admire, but whose actions we hate and deplore. These contradictory reactions to him suggest something of the duality of his own nature. For example, he resents being insulted and yet consciously places himself in a position where he cannot avoid being insulted. Throughout Part 1, we are exposed only to the Underground Man's ideas; they are the thoughts and conclusions of an intelligent man, no matter of what age or century. In contrast, Part 2 depicts the Underground Man's actions in relationship to other people, and they are spiteful and deplorable acts.
To return to Part 1, we admire a man who refuses to accept scientific rationalism when an acceptance involves the destruction of man's individuality; we agree with him that human freedom — that is, the freedom to choose one's own way of life regardless of the consequences — is more important than the life of a robot. We accept his idea that only the individual can choose what is to his best advantage. We acknowledge the validity of his view that while science has improved living conditions, it has not changed the basic desires of man; and we are aware that the human personality is composed of both rational and irrational desires. Furthermore, we enjoy and concur in his criticism of scientific utopias, of progress, of utilitarianism, and of other assumptions made by modern civilization. As humanists, we are in accord with almost every proposition he advocates in Part 1, even though he argues them in a spiteful manner.
By contrast, in Part 2, we are repulsed by almost every action undertaken by the Underground Man. As an intellectual advocate against scientific rationalism, he was a voice arguing in a void and we could concentrate on the validity of the arguments without confronting directly the warped and distorted personality of the speaker. However, in Part 2, we see directly his failure to function as a human being in his own society.
The Underground Man told us in Part 1 that, in his dreams, he could take an unintentional slight and magnify it into an outrageous insult. In Part 2, we see that his fragmented personality will allow him to experience things only vicariously; contact with real life is impossible because of his extreme fear of reality.
Ultimately, his fear of being ridiculed, rejected, or scorned causes him to demand complete domination and even tyranny over any friend or any person in any relationship. He could be friends with Zverkov only if he can dominate Zverkov, an impossible task. This need to tyrannize others results from feelings of inadequacy caused by his over-refined sensibility and his over-acute intellectual awareness. The Underground Man's intentional attempts to subjugate Liza show his spiteful, twisted, despicable nature.
Finally, even though we agree with his ideas in Part 1, the final view of this refugee from humanity is that of a twisted deranged soul who deserves no compassion and who should exist in an underground hole.