Concept · Cognitive Bias: Informal fallacies of relevance
Guilt by association
Origin: Traditional; 20th century formalization
Biological Parallel
When one member of a meerkat colony contracts parasites, others avoid grooming that individual and its frequent associates. This associative avoidance is adaptive—parasites and pathogens cluster in social networks, making proximity a valid infection risk predictor. Humans inherit this pattern recognition: we evolved to avoid individuals connected to threats because, in ancestral environments, social clustering of danger (disease, aggression, resource depletion) was statistically real, even when logically invalid for specific claims.