A productive conversation is one where people make concessions from their best position, and come to a consensus about what they know, what they dont know, and the parameters of future negotiation.

There is no such thing as "Truth" beyond consensus. That's what a productive conversation is-- the reaching of consensus on the relevant facts. This is why legal briefs begin with a statement of the facts, and the reply brief proposes a counter statement that accepts, or demurs to, the factual averments set forth in the complaint.

I've negotiated many contracts, settlements, and plea agreements. The parties rarely care about "objective truth."