Congruence bias is when our brain wants things to be the same, or congruent. Kind of like how we want our socks to match or our puzzle pieces to fit together.
But sometimes, our brain can take this too far and we start to think that things are true just because they fit with what we already believe. It's like when we only listen to people who agree with us instead of considering different opinions.
This can make us miss important information or make bad decisions. So, it's important to be open to new ideas and information, even if they don't perfectly match what we already think.