Concept · Cognitive Bias: Formal logical fallacies
Affirming a disjunct
Origin: Traditional logic
Biological Parallel
Survive winter by migrating OR hibernating. Monarch butterflies migrate 3,000 miles. Therefore they do not hibernate. But some monarch populations demonstrate phenotypic-plasticity: partial migration with local dormancy in milder winters—bet-hedging against variable conditions. Arctic terns migrate pole-to-pole; European eels cross the Atlantic; sockeye salmon return upstream—each shows geographic-migration as default. Yet migration-selection-balance allows hybrid strategies when payoffs overlap. Affirming a disjunct assumes mutual exclusivity where none exists. Evolution does not respect 'or'—it explores combinatorial innovation. Exclusive categorization misses the real playbook.