When thrust into a conversation with someone who sees reality in a different way, “progress” or, rather, not-ending-up-hating-this-person can feel impossible. If basic facts can’t even be agreed upon, how can anything positive occur? What this question incorrectly implies, though, is that no basic facts of agreement exist when they do. Or at least agreement on something should exist if you are the open-minded, just calling balls and strikes person you surely claim to be.
First, step back from the toxic issue (TI) and pivot to a place of shared condemnation. How to find such a place? Well, apprehend the reasoning error your counterpart is making re: TI. A quite common one is making an unfalsifiable claim1 or making a claim that seems falsifiable only to perpetually change the falsifying metric whenever the thesis appears falsified,2 but any error will do. It’s important to appreciate that your counterpart almost certainly agrees that reasoning errors are, in fact, errors, but that his own biases will prevent him from easily witnessing his mistake re: TI.