Me thinks Mr Horse is correct on that much...
Yes this is true, but each one of us thinks differently and it's our differences that stand in the way. If we listen closely to those who actually do not think, they bring a value to us as humans.
Donkey's have never been thought to be intelligent, only I believe because we addressed them as Jack Ass, and kept thinking they were stupid because of the way they acted. Today they are intelligent and loyal pets.
As far as changing people's thinking. When the groups dissipate from bringing them to one belief will each person realize their are better options.
I've given up on changing people's thinking long ago as it's futile, and you are right each individual has their own unique way of thinking. As for the groups in this world, while alot of bad things can come from groups there are some positive things as well, I'm largely a loner myself but at times even I find groups to be beneficial. I get your point though.
Especially true when dealing with religious zealots.