How do you change a person's opinion?
The opinion we hold about each other may seem like an opinion, but it is actually like a big tree with a very complex root system. Behind an opinion is a set of interpersonal relationships, past history, patterns of interest, values, and ways of acting. It is far more complex than outsiders can imagine.
Everyone is not easily changed, and if you want to change a certain point of view of a person, you actually have to change everything he has experienced and everything he has thought in the first half of his life.
So, to change someone's opinion, it is too difficult to work by the tool of presenting facts and reasoning. It doesn't have that much power.
I recently read that changing a person's perception is not about creating a new concept that he never knew before. Rather, to state a consensus that he was not aware of before. Very enlightening.