 Philosophical discussions of dreaming tend to focus on (a) dream deception and (b) questions about the ontology of dreaming, its moral status, etc., that tend to intersect with dream skepticism. By contrast, the main source of interest in dreams outside of philosophy traditionally has been dream interpretation and whether dreams are a source of knowledge and insight. Historically, the epistemic status of dreams and the use of prophetic and diagnostic dreams was not just a theoretical, but a practical problem (Barbera 2008). Different types of dreams were distinguished by their putative epistemic value. Artemidorus, for instance, used the term enhypnion to refer to dreams that merely reflect the sleeper’s current bodily or psychological state and hence do not merit further interpretation, whereas he reserved the term oneiron for meaningful and symbolic dreams of divine origin.