People and their opinions

One thing that has been on my mind lately is how people state their opinion as fact and then back it up with "well that's just my opinion" as if that settles it or something. Case closed, I have stated my opinion, which is mightier that yours so I win. No facts to back up their opinion, or experiences to speak of, nothing. Just a "well it says it in the bible" or "that's what my pastor told me" cool. I am actually cool with that. Just do me a favor first, LOOK IT UP FOR YOURSELF. People can say anything they want, and just because someone you trust told you something doesn't mean it's true. I'm not trying to bitch, I'm just blowing off steam, mainly because if someone wants to discuss something with me, they could at least have a general idea of what they are talking about. That would be nice.