If you quietly make a few good points, don't push too hard, and ask sincere questions to help you understand the other person's perspectives, the average human will think "that guy is a class act. He had a good point, too."
Convincing anyone other than a hyper-rationalist of almost anything significant is more about emotions than it is about cold, hard facts.
And most humans, for better or for worse, are emphatically not hyper-rationalists.
