When was the last time you changed your opinion?
It's not easy to keep an open mind all the time. I mean, we all have our moments of stubbornness and thinking we know it all. A lot of people will treat the possibility as certainty, and when you disagree with (usually) personal experience that is not applicable to everyone, they will feel attacked and shut down.
Don't be like them! It's always good to have a bit of scepticism, but don't let it turn into cynicism. Remember that true wisdom lies in the ability to hold multiple perspectives and to learn from the experiences of others.
Next time you find yourself in a disagreement, try to listen without waiting to speak. Let the opposite side disagree with you, and then take it in and don't defend your point of view. Take a moment in peace and try to get to the point of "why" you believe what you do and how it is different, and ask yourself: "how do I KNOW I am right?"
Also - don't take yourself too seriously. You (we) are not that special. So, be open to change - and if anyone tries to belittle you for things you don't know, just remind them that the journey of self-discovery is a lifelong process, and you are just getting started.
There's nothing wrong with being in the wrong!
But, if you are not a different person every few weeks / months / years - you are doing it wrong.

