Remember back when the Underground Man said he couldn't become anything? He elaborates: he couldn't even become an insect if he wanted to.
Why? He is too conscious. Not only is he cursed with hyper-consciousness, but he's cursed with having to live in St. Petersburg, which is "the most theoretical and intentional town" in the world. (He's probably referring to the fact that St. Petersburg was set out in a grid of streets and squares; in this sense it was theoretically plotted and hyper-conscious in its conception. (Think Denver's orderly grid of roads as opposed to Boston's sideways cow-paths made halfway into highways.) It was also 'theoretical' in the sense that it was stuffed to the brim with romantic intellectuals, who would talk about silly abstract things.)
He adds that he is not writing this to be witty; after all, his hyper-consciousness is a disease, and who can take pride in his disease?
Well, come to think of it…everyone. In fact, the Underground Man adds, any kind of consciousness (not just hyper-) is a disease.
For example: at moments, the Underground Man can come close to feeling and appreciating "the sublime and beautiful." (This is a cliché from academic circles of the time because of a text by Immanuel Kant. In simple terms, Kant examined the scary or fuzzy feelings we get inside when we come in contact with the sublime or beautiful stuff in the world.)
Unfortunately, at these moments, the Underground Man starts doing ugly things.
The more aware he becomes of goodness, he explains, the more he "sinks into mire." It got so bad he stopped struggling against his own depravity.
This was pretty agonizing for a while (read: boxes of tissues, Ben and Jerry's, chick-flicks), especially since he figured he was the only one going through this.
But then, gradually, somehow, the horrible agony turned into sweet, sweet enjoyment.
What? Fortunately, the Underground Man explains this a bit more: the enjoyment came with him knowing that he was being degraded, from knowing that he had hit rock bottom, that there was no escape, that things were so bad, he could never, ever be a different man.
Besides, even if he could change himself and fix things, he wouldn't want to.
Besides, even if he wanted to, there isn't anything for him to change into. And to realize all this is enjoyable to him.
(Someone needs to buy this guy a Playstation. Or a friend.)
This next part might seem a little tricky, so bear with us: the Underground Man has been talking about his hyper-consciousness, meaning he's aware of and has to analyze every little impulse, feeling, desire, emotion, and thought that he has. Now he refers to "fundamental laws of over-acute consciousness," and he says they result in "inertia." What he means by "laws" is that his hyper-consciousness (the same thing as over-acute consciousness) governs the way he behaves. And these laws cause inertia, which is a tendency for things to stay as they are. So in a nutshell: because he's hyper-conscious, he can't change. He'll keep using these terms (especially "inertia,") so we'll chill out for a minute while you make sure you're good to go with those definitions.
And we're going. Fortunately, the Underground Man is able to conclude from all this that he can't be blamed for being a jerk; it's not his fault, it's the fault of his over-acute consciousness.
The Underground Man explains that he also has a good deal of amour propre. This means "love of one's self," but with the connotation of the same over-acute awareness and self-consciousness that we've already been talking about.
Still, despite this love for the self, he would probably be happy to get slapped in the face, because then he would find the enjoyment of despair that you can only experience when you are very aware of your own crumby position.
He adds that, actually, he is to blame for all this, but NOT because of his own faults, rather because of "the laws of nature." (And we think he needs to work on his definition of "blame," as it tends to go hand in hand with "fault" as far as we know.)
He clarifies: he is to blame because he's cleverer than most people, but that isn't his fault.
And even if he were magnanimous ("big hearted," like a mix of "brave" and "kind"), he would suffer from the understanding that magnanimity is useless, which would render him unable to act on his feelings of good-will.
Let's go back to the slap-in-the-face scenario. If he had been slapped in the face, he's smart enough to know that his assailant only slapped him because of the laws of nature. Since you can't forgive the laws of nature, he wouldn't be able to forgive the assailant.
Besides, he says, even if he wanted to act on his fuzzy happy feelings of magnanimity, he wouldn't be able to, because he can never make up his mind to do anything, like slap the assailant back.