Disagreement is normal. It can be a positive thing. It is how a person deals with disagreement that is important. Though not being aware of Critical Thinking/Logical Fallacies etc can make things that you SHOULD logically disagree with not be disagreed with simply because of failure to see the logical fallacies being used against you/us. So it is important to understand Generalizations, Appeals to Authority, Ad-Hominem attacks, Red Herrings, Bandwagon, False Dichotomies, etc.

There is a positive aspect of knowing those too. It gives tools for discussion for when both sides are aware of logical fallacies they can cut through the bullshit/fluff that is all smoke and mirrors and just get down to the issues.