Everyone has a right to his or her own opinion is one of the most frequently misused and abused phrases in the English language.
All right, so technically the Thought Police don't actually exist and you can't be sent to Room 101 for having an opinion contrary to those in power. I get it. But there's more at stake here.
Everyone has the right to be secure in knowing he or she won't legally be prosecuted for his or her own ideas (unless of course said ideas infringe on someone else's rights to a patented idea, but that's another tangent). But in truth, your right to hold an opinion is relinquished when it conflicts with your epistemological duty to configure your beliefs so that they correspond with evidence and facts readily found in the surrounding world.
This illusory truth has deeply entrenched itself in American culture. It is one of the unfortunate symptoms of an irresponsible participation in democracy. If you're brought up believing in the ideals of the democratic vote and taught that you have a protected freedom of speech, but you don't engage in meaningful self-evaluation and critical thinking, you come to expand this statement from the realm of law to the realm of reason. That is a dangerous conceptual equivocation.
Yet many of us participate in this kind of conversation all of the time. We shift our legal right to say whatever we want (well, almost whatever we want) to an epistemic right to hold a belief in the face of disagreement, even when the disagreement centers on a crucial recognition, or lack thereof, of facts or valid reasoning.
Let's construct an example, shall we?
Suppose that someone makes a claim that racism and segregation died away in the United States in the 1980s. In response to this hypothetical individual, I point to a news story reporting on a racist theme party that happened at the University of California at San Diego this past February - a fact which actually contradicts the opinion-based claim he or she made (as in, the party actually happened, is actually racist, and it actually took place post-1980s). Would it not be within this person's right to respond that everyone has a right to his or her own opinion, so we should just leave our little disagreement at that?
Absolutely not. That is the misrecognition of fact for opinion, at best. At worst, it is a refusal to accept facts that contradict one's own beliefs. Either way, it is wrong.
There is nothing wrong with being wrong. Each one of us is wrong on myriads of occasions - myself definitely included. However, opinions are, or at least should be, fluid entities, ready to change shape in accordance with recognized evidence.
So yes, we all have a right to hold opinions. Nobody's going to deny that. But along with a right comes a duty. In order for our right to hold opinions to remain legitimate, we must act in accordance to the duty which logically follows: We may hold opinions so long as we remain intellectually honest in how we integrate new evidence into our belief systems.