The 10 Guidelines on Epistemic Hygiene and Social Dynamics

If you believe that someone is being disingenuous or crazy, then it's important to be extra cautious and principled about how you go about discussing this fact. Openly and explicitly acknowledge that you are in fact making assertions about the interior of another person's mind. Do not just assert that you think this is true, include quotes and references that show what led you to generate the hypothesis. This gives the other person more space to be visibly shaken or upset without creating the appearance of proving your point. It helps diffuse the threat vector by which one person provokes another into appearing unreasonable/hysterical and thereby delegitimizes them. A blanket ban on hypotheses about others' internals would