Key Insight

One reliable sign that a discourse has left genuine inquiry and entered cultural conflict is the appearance of the accusation: anyone who disagrees must be acting in bad faith or secretly allied with the enemy.

The title refers to a pattern that recurs across ideological divides: the substitution of identity labeling for argument. When a participant responds to evidence not by engaging with it but by attributing the source's position to ideological contamination, the conversation has shifted from science communication to cultural conflict.

Bans & Decibans

A ban is a unit of evidential weight in Bayesian reasoning — the base-10 logarithm of the Bayes factor. A deciban is one-tenth of a ban. These units provide a precise vocabulary for discussing how much any piece of evidence should shift our beliefs.

Identity-protective cognition operates by subverting Bayesian updating — causing individuals to weight evidence not according to its actual probative value but according to its consistency with identity-defining group positions. Understanding evidence in terms of bans and decibans forces the question of evidential weight into explicit view, where it can be evaluated on its merits.

"The question is never whether you agree with the conclusion. The question is always: how much should this evidence shift the probability you assign to competing hypotheses?"