I'll throw out the theist/atheist debate as an example.
The answers aren't easy and semantics cloud the issue, but there is a reality.
Both positions cannot be simultaneously true.
I believe they can.
For example, if 'you' believe in god, then god exists...................for you.
If 'I' don't believe in god, then god doesnt exist.......................for me.
So it just becomes 'you should think as I do' for both parties.