Of course, because The Idiot is set in the 19th century, there are the usual culprits who abuse the economic or class superiority they have. In this novel, however, a lot of power is also wielded by the ostensibly powerless characters who use their victim or outsider status as a way to cause social disruption. These have-nots represent the danger of shaking things up for the haves, which protects them from the usual manipulations of those in power.
Power is shown to be fluid and easily transferrable from person to person. Those in close relationships are constantly experiencing shifts between who is the more powerful. It is the ability to cope with this back-and-forth that makes or breaks the relationship.
Paradoxically, the most powerful people in the book are those who are most able to renounce it.