Paternalism is an action that limits a person's or group's liberty or autonomy and is intended to promote their own good. Paternalism can also imply that the behavior is against or regardless of the will of a person, or also that the behavior expresses an attitude of superiority. Paternalism, paternalistic and paternalist have all been used as a pejorative.

Soft paternalism is the view that paternalism is justified only if an action to be committed is involuntary. John Stuart Mill gives the example of a person about to walk across a damaged bridge. We cannot tell the person the bridge is damaged as he does not speak our language. According to soft paternalism, we would be justified in forcing him to not cross the bridge so we could find out whether he knows about the damage. If he knows and wants to jump off the bridge and commit suicide then we should allow him to. Hard paternalists say that at least sometimes we are entitled to prevent him from crossing the bridge and committing suicide.

Moral paternalism is where paternalism is justified to promote the moral well-being of a person(s) even if their welfare would not improve. For example, it could be argued that someone should be prevented from prostitution even if they make a decent living off it and their health is protected. A moral paternalist would argue that it is ethical considering they believe prostitution to be morally corrupting.

More Info: en.wikipedia.org