being an ex-philosoper, I even differentiate between 'excuse' and 'explanation'. I don't dare assume that anyone who disagrees with me is 'stupid', so I have to look elsewhere for an explanation for views I consider indefensible. Some people just develop some emotional/social/religious/fiscal..etc. attachment to a set of beliefs so deep they they are unable to see other viewpoints. They decide what the answer MUST be, then twist all logic, facts and discussion to fit. This is pretty shallow reasoning, but it 'explains' why people who are pretty smart can hold stupid opinions.

It is one of the mysteries of life how folks can look at the same set of facts and come up with totally divergent opinions.