It often helps me to remind the word "respect"...
There are people that are open to well founded disagreement and there are others, usually many many more, that won't let you express your opinion, they tend to be monologuists therefore deaf to what you have to say.
I stick with the respect mood as far as it's possible and step back when we arrive to a not ending point.
Cheers
Agreed! Respect is an important part of civil discourse. It's often also the key difference between "making a point" and merely "silencing dissent," as the path to "proving" a point.