Concept · Cognitive Bias: Informal fallacies of relevance

Appeal to incredulity

Origin: Modern formalization

Biological Parallel

Octopuses can edit their own RNA to adapt to temperature changes—a mechanism so complex that early researchers dismissed reports as errors. Yet our intuitions about biological complexity are calibrated to visible, macroscale phenomena our ancestors could observe. The appeal to incredulity exploits bounded cognitive capacity: if we can't mentally model a mechanism, we assume it's impossible. Evolutionarily, this heuristic worked because most claims beyond direct experience were indeed fabrications. Science now routinely discovers mechanisms (quantum biology, epigenetics) that exceed intuitive complexity limits.