the famous system of solitary confinement also achieves only a false, deceptive, external purpose. It sucks the living juice from a man, enervates his soul, weakens it, frightens it, and then presents this morally dried-up, half-crazed mummy as an example of correction and repentance.
Dostoyevsky's amazing criticism against the penal system but this has a metaphorical interpretation to it, and it shows the most through characters like the Man with The Ridiculous man, and probably even Raskolnikov. The Karamazovs even deal with this theme.
Yes, this is a theme but it ties in with the third one.

