I used to believe that "second hand smoke" came from smoking two cigarettes at one time, one in each hand. If smoking was bad for you, second hand smoke was worse.
A childhood belief about smoking

others believed things like this
- I thought second-hand smoke was bought off eBayAnon
- I used to think that my dad was "smoking pot" when he would smoke his pipe while sitting on the toilet. Anon
- A friend on mine thought that smoking menthal cigarettes would make his breath minty fresh.Anon
- I used to think that my right hand wasn't my right hand anymore if I turned around.— Mike
- all people who smoke roll up cigarettes have been to prison— spam
- I used to believe that smoke stacks that pumped out white smoke were cloud makers.— lizzie