Are psychedelics bad for you?

i know they can cause psychosis and paranoia but i honestly believe they help you retain past memories. i once gave a guy a hit of acid (i have only done psychedelics seven times) and he went to a quiz bowl in oxford mississippi and he didnt miss a question. he was able to remember things that he hadnt remembered in a long time....i really like joe rogan and terence mckenna and their philosophies on life