When Does an Opinion Become Wrong?

We've all heard of opinions before.  Mainly we've heard things like "there's no such thing as a wrong opinion" and "everybody has the right to their own opinion".  Technically, I agree with these statements, however I disagree with what many people believe are opinions.  So to use the commonly accepted definition of an opinion, "a view or judgment formed about something, not necessarily based on fact or knowledge", Let's take a look at exactly what could make an opinion wrong.

We can apply two different definitions of "wrong" to an opinion: logically incorrect and/or morally wrong. Logically incorrect opinions can be easily shown to be such, just by analyzing the argument in question.  However, when many people say someone else's opinion is wrong, they usually mean the latter definition, that the opinion is morally wrong.  Looking back at my argument against objective theories of ethics, we can't say with any certainty that an opinion is, in fact, wrong.  Besides, opinions are nothing but judgments reached by people, and these judgments don't have to be based on knowledge or information.  As such, an opinion is independent of knowledge, and can never be proven wrong.

What changes then?  If we base our actions on our opinions, how is it that we can try to judge an action as right or wrong?  In the scope of relativism, we normally can't even do this.  We can, however, look at it in the context of cultural relativism to determine whether it is wrong for a given set of agreed-upon morals.  But how can an opinion, when not based on knowledge, be truth apt?  What changes when we decide to act on an opinion?

When we act on an opinion, we convert that opinion into a statement of fact.  If I slap someone because I think they're a bad person, I cease merely being of the opinion that said person is bad and start believing my opinion to be absolute truth, enough so to justify a physical attack.  It stops becoming an abstract, personalized view and becomes a statement of fact that everyone else has to deal with as well.  When others have to deal with an individual's opinions, they are no longer opinions, and become morally relevant. As we tend to default to one of the objective theories in the process of cultural relativism, we try to define someone's reason behind an action to be either right or wrong. Thus, what was once considered to be merely an opinion now becomes right or wrong.

Yes, opinions, as defined here, can't be wrong, and everyone has the right to their opinion.  Acting on said opinion is what makes that opinion either right or wrong.