I often face resistance when I present people with the statement, "Your opinion is wrong." The backlash or counter point is always that an opinion is how "I" feel and "I cannot feel wrong," But, the simple fact of the matter is that you can. You can absolutely feel wrong.
So, let's expand on this.
I think that to understand how an opinion can be "wrong" or invalid we have to first understand opinions. You cannot just say anything you want or think or feel and then call that an opinion because that simply isn't what an opinion is.
On a very basic level, an opinion is an interpretation, judgment or belief that can be neither proven or disproved. If you can prove it (with objective proof, of course), it's a fact. But, there are really two different types of opinions, expert and informed. The expert opinion is hard to refute unless you claim to be an expert when, in fact, you're not. It's the informed opinion that causes the most trouble.
You can have an informed opinion, which you develop by gathering and analyzing evidence. But, Wikipedia does not an informed opinion make. The evidence that you gather MUST be unbiased and factual in nature. So, you have to distinguish fact from fiction. And, False Facts can be difficult to uncover. You also have to look at an issue from both sides (again, unbiased information) before making a judgment. If you base an opinion on a False Fact or biased "evidence", your opinion is wrong. If you only understand one side of an issue, your opinion is invalid.
For example, if you say that you do not support vaccines because they cause autism, your opinion is wrong. There was one study that said vaccines caused autism. The study was debunked and the doctor who published it lost his license to practice medicine. Also, the ingredient that was identified was removed from vaccines some time ago. Since 2003, nine separate studies have found no link between vaccines and autism. So, that opinion is simply wrong. Can you say that you do not support vaccines because they have scary side effects? Sure. Absolutely. Some can cause death. That's scary. That's factual. That opinion is valid.
Though, if your opinion was that you do not support vaccines because they cause autism during the time where there was a valid study, the opinion would not have been wrong. So, if someone were to publish something in the future that invalidates the nine aforementioned studies, the opinion might again become valid.
We all know that sometimes scientific data winds up being wrong. Pluto is a planet. Pluto isn't a planet. Pluto is a dwarf planet. Or, take for example, the brontosaurus (Remember "Little Foot" from The Land Before Time?). But, then scientists realized they maybe just had an Apatosaurus. Tomorrow they may realize that they were right the first time. We can't anticipate that. We just have to base our opinions on what is currently considered a fact.
I see so many arguments on the internet that are baseless. I see so many people whose opinions are flat out wrong. They're unsubstantiated. Is Obama to blame for the price of your health care? No. Did he propose the Affordable Care Act? Yes. Is the act he proposed the one that came to be? No. It was modified before being approved. Are the hikes in price a direct result of the act? Not really. It's the administrative costs or the drug costs that hike your health care rates. It's things like the fear of law suits or or wages or branding that hikes the cost of care in the U.S. So, can you say you don't like the Affordable Care Act? Sure. I'm sure there are a plethora of valid reasons to have that opinion. But, can you say you don't like it and blame Obama? Not really. The result of his proposal wasn't actually his proposal.
We can apply this to many arguments people make. We can apply this to whether you like or dislike our current President-Elect. Can you have a valid opinion for liking Donald Trump? Sure. Can you also have a valid opinion for disliking him? Absolutely. But, those opinions must be based in fact. They must use unbiased sources as support. You, as the opinion-holder, must understand both sides of the coin before having a valid opinion.
