'You cannot reason people out of an opinion they have not reasoned themselves into.'
That's a modern way of saying what Jonathon Swift observed in 1721.
The research makes it clear that our reasoning is not entirely logical - but we think it is.
We treat our own opinions as more logical and well-informed than other people's opinions. We may not go as far as talking about alternative facts and rejecting other people's information or opinions as fake news, but it's only human to struggle with objectivity.
How much of a struggle?
Psychologists have studied more than 90 ways we humans compromise our objectivity. Let's look at a selection.
Let's say you are in a meeting. You want to persuade your colleagues to see the benefits of sharing a digital calendar.
Your presentation seems to be going well. Then Fred leans back on his chair and announces, 'It's not worth the hassle. My diary works well for me. I'm not changing.'