...[U]nder tribal morality, principles are subsumed under tribal membership....
Tribal epistemology happens when tribal interests subsume transpartisan epistemological principles, like standards of evidence, internal coherence, and defeasibility. “Good for our tribe” becomes the primary determinant of what is true; “part of our tribe” becomes the primary determinant of who to trust.
A circular logic, which has become quite familiar in the impeachment affair, emerges: Anyone who says anything contrary to the tribe marks themselves as an enemy of the tribe....; enemies of the tribe cannot be trusted, so their testimony or evidence can be ignored. Thus, by definition, nothing that questions the tribal narrative can be trusted.
A decades-long effort on the right has resulted in a parallel set of institutions meant to encourage tribal epistemology. They mimic the form of mainstream media, think tanks, and the academy, but without the restraint of transpartisan principles. They are designed to advance the interests of the right, to tell stories and produce facts that support the tribe. That is the ultimate goal; the rhetoric and formalisms of critical thinking are retrofit around it.