Altered presumption of real objects is

(A) Illusion # Hallucination-- caused by a substance; seeing and/or hearing people, objects that are not there & verbally responding to them.> Delusion--false idea; misbeliefs (example) thinking one is a king or God or the president. Ideas of grandeur.> Illusion-- seeing an object that isn't there; misconception of looking at something, but seeing it as something other than what it really is. (E.g.) a puff of smoke may look like a ghostly figure or a tree trunk with branches, may look like a person with arms extended.