I'm referring to people who do as you have done here (others do it too) and instead of simply saying - eg 'I think you are talking bunk' go on and on ad infinitum to get someone to respond in a way they feel satisfied with.
Sometimes we may have to sigh and walk away - doesn't mean you have to accept the other view just be resigned about it.
Divebuddy, invincible ignorance can be argued against, but never conquered. There's a clue in the name. According to our RC friends the sin (invincible ignorance, I mean) is venial, not mortal.
divebuddy - //V_E. Sometimes I think (as Mamy seems to suggest is the right thing to do) that letting things go is simply letting the imbeciles run the sanatorium. //
I prefer to think that sometimes you simply cannot make your point understood, so the sensible option is just to walk away.
I don't think it leaves anybody 'running' anything.