It's hard to change your mind once it's set. It's also surprisingly easy to set your mind when you still don't have an opinion. Depending on the source you probably fix your mind to the first "fact" you hear about the matter or decide to oppose it. After that nothing can change that fixation anymore. At least not easily.
We have elections coming here in Finland. Time to once again choose your party and try to find a suitable candidate among all those that promise so much. While trying to find one for myself I have noticed those biases in me. I have my own opinions, principles and even prejudices. Even if I try to keep my mind open I have caught myself skipping candidates despite all those election quizzes giving high match between our opinions, just because they represent the wrong party.
I have also noticed I have started giving different answers more I do those quizzes. I try to match my answers more on those that my "chosen" candidate would answer.
It's subtle, I almost missed it. But even being aware of those things it's easy to fall for them if you are not careful. Luckily I realized it before it would have been too late. This time I have chosen differently. I changed my mind.