When you consider the life experience of the person you are engaging, ethnic background, lack of previous exposure to the same body of knowledge that you have - lack of common reference as it were, and these same considerations apply to yourself as well, then you should be able to "see" that you and the other have arrived at the best conclusions possible, given limitations. From this point on, a shared learning experience is possible ...

There is no debating long established truths .. ie. flat earth vs round .. what I refer to is more in the realm of belief, and the increasingly complex. The person who believes themselves 'absolutely correct', waveringly so, is usually not so much, and not very interesting. :)