The more important question isn't "are you correct," it's "does it matter to be correct right now?"
Maybe you do actually know better than everyone else, but why do you have to prove it to others? You can just quietly make your argument and shut up. It's their loss, and people may remember that you were right.
Maybe it's about an important decision at work, but if your correctness pisses everyone off, no one is going to listen to you again. You've won the battle but lost the war.
People shouldn't be that way, but they are.
> You can just quietly make your argument and shut up.
This is generally the right approach, unless you're on the hook for the consequences of whatever the group decides. Continuing to argue a point that you've already made isn't likely to change any minds that weren't open to it the first time you said it. I think that's even in the HN guidelines.
If you're the one responsible for a decision, listen to what others have to say but if you still feel strongly that your contrary view is correct then go with that and live with the responsibility.
I like this answer. For me it's not about showing others that you're correct. Instead, it's about feeling like you're being heard/acknowledged.
I'm not trying to be the "lone free thinker". But if I see a hivemind, I occasionally insert my opinion with the intention of having a different perspective be recognized.