Hi Don,
The psychology answer of the question you posed has been known for some time. It comes down to when a person makes a statement or verbally agrees with somebody, they commit themselves to that answer even if they later find out that it's wrong. Pyscologies such as Robert B. Cialdini have done many studies on this human phenomenon. Charlie Munger in his "The Psychology of Human Misjudgment" (
link to PDF) -- He cites Cialdini, Books such as Predictably Irrational, and even The Black Swan cover this error human tendency.
Now to answer your second question, can we sit down and drink coffee/espresso with somebody we so drastically disagree with or are we resigned to not talk.
I once read a quote that went something like
"People do not remember what was said but rather how they felt"
The answer is yes, the trick is to not allow emotions to overrun logic and rational, which is not so easy to do.
=X=