48% of Americans claim they believe in ghosts and about a quarter say they’ve actually seen one. Whether you’re one of them or a firm non-believer in paranormal activity, we’re all a bit curious to find out if there is any actual proof of the existence of ghosts. This video explores this question, as well as the various scientific explanations for why people think they see ghosts. So even if ghosts don’t exist, it doesn’t necessarily mean you haven’t seen one...