Scientific entities like X-rays and black holes defy firsthand observation and everyday intuition, yet most people outside the scientific community still believe in their existence. Upon what kind of epistemic foundations do such beliefs rest? The present study explored this question by comparing students scientific beliefs to their supernatural beliefs along four dimensions of epistemic import: confidence, perceived consensus, means of justification, and openness to revision. Participants scientific beliefs were strongly differentiated from their supernatural beliefs along the dimensions of confidence and consensus but only weakly differentiated along the dimensions of justification and revision. Moreover, participants confidence in both types of beliefs was predicted by their consensus estimates but not their ability to cite evidence in support of, or potentially in conflict with, those beliefs. These findings imply that students scientific beliefs are no more epistemologically sound than their supernatural beliefs, despite self perceptions to the contrary.