How do you work with an individual who _insists_ they understand how it all works? Even when faced with hard evidence that contradicts their assessments, I'm still told I don't understand or I misinterpreted their words - basically gas-lighting me. Arguing leaves me unmotivated and frustrated. Giving in is the wrong path. Going to others doesn't seem to move the needle. Help.
Document, and shut up. Document every time they say something false - time and date and medium, and exact words. Shut up: for each instance, say once that they're wrong, then don't argue. When it matters, when there's a decision where this person's view is threatening to sway matters in the wrong direction, go with a massive documentation dump - everything they've said on the subject, exact words and date and time an…
At some point employees shouldn't manage other employees. Dealing with this person is the manager's job so as a coworker don't try to do it.