What did David Hume denied that existed?

Answer 1

David Hume denied the existence of innate ideas, arguing that all knowledge arises from experience and sensory perception. He contended that human understanding is limited to impressions (direct sensory experiences) and ideas (mental representations of those impressions), thereby rejecting the notion of a priori knowledge or concepts existing independently of experience. Additionally, Hume famously questioned the existence of causation and the self, suggesting that our understanding of these concepts is based on habit rather than rational certainty.