Well, if when you believe something it makes it a fact, then yes, I agree with what you just wrote. However, if you understand that what you believe in is merely your perception of reality, then no, I disagree with what you wrote.

As far as ignoring others' opinions, yes I do this often. For two reasons: I can't win the argument, or other people's opinion are irrelevant. Usually, it's self evident which category opinions fit. But sometimes, people are just dense.