Lines get drawn. Folks take a stand. Heated debate ensues. Which is healthy.
Do you change your views and concede a point or two if you realize the other side presented you with facts unknown to you? Or do you dig in your heels to fortify the defence of your position?
I agree with Gora Kala. Human nature makes it very difficult to accept that you were wrong, even after being presented with the facts. But only when you do that, you can truly change your views accordingly. It requires a lot of character to do that.
The assumption here is once you are presented with "true fact". Yes your response is the right one. How many people can bring themselves to say those words?
Naturally, you would go off what you know at the time. In the future if it turns out to be wrong then its ok to admit you was wrong. I have no issues with it and would accept it.