I used to believe that arson was a flammable liquid, not the act of deliberately setting fires.
A childhood belief about criminals

others believed things like this
- I used to believe that the Fire Station was where all fires occurred.Anon
- I thought that hot water couldn't put out fires.— Matt
- I used to believe that firemen drove around in their fire trucks and started fires. I wondered why.— Albert
- I used to believe that house fires were caused by foolish people who put paper on the stove.— C.C.
- To clean the goldfish you put washing up liquid into its bowl.— Sev
- I used to believe that the reflection at the bottom of cup of liquid was a crocodile waiting to gobble me up.— Aaron