I hate being wrong but I love learning. Of course, the only way to learn is to find out you were wrong about something you (thought you) knew.
There are a couple of ways to be wrong. One is to stomp your feet, cover your ears, and refuse to admit it (which breeds discontent in others and damages trust in your relationships). The other way is to do your due diligence, graciously accept the lesson, and be excited for having learned and gained more power with new knowledge.
Here is how I exercise Option Two:
I research what I thought (or assumed) was true. More importantly, I check sources and trust peer-reviewed literature above almost everything else (searching Google Scholar is an easy way to find peer-reviewed literature).
Peer-reviewed literature is not foolproof, of course, but it is the closest thing we have to proving something is true. It means other people with significant knowledge on the same topic and an understanding of the scientific method have tried to poke holes in an idea to see if it seems to be fundamentally true.
Like most people, I sometimes make the mistake of believing something I have read or watched because it seems legitimate, it is presented in an emotionally convincing way, but I am too lazy to do the grueling work of learning about a complicated topic (like the paranoia around genetically modified food, for example) and fact-checking, and then validating the source material again and again. It is so much easier to just believe what someone tells me, especially if they look or sound like they know something.
Also, some things I have believed for so long (that is, from when I was more susceptible and less skeptical) that I have adopted them as truth–but just because something is old and believed by many does not make the thing factual. Sometimes I have to check (or double-check) an old belief or assumption to find out if it still seems true to me (by the way, isn’t this how you learned the real story behind Santa?).
Today’s lesson, then, is this:
If someone suggests you are wrong, do not go straight to defense. Just do your homework, find peer-reviewed literature that supports or refutes your claim (or theirs), and accept the consequences. If it turns out you were right, be gracious and respectfully share or validate your findings. If it turns out you were wrong, then be gracious and respectfully share or invalidate your findings so others do not make the same mistake, and be excited you busted a false belief (even if you busted yourself in doing so).
Put more simply: you can not gain intelligence by refusing to learn.