To begin, you need a bit of background on my family: Dad's a lawyer, Mom's a medical researcher. And they're a bit careless with their references.
Anyway, I found a book called the Amazing Machine about the human body, and, being at the time in my machinery-fascination stage, started reading.
Then after dinnertime, I sat at the table and waited for several minutes. When Mom noticed me, she asked what I was waiting for.
To which I replied, "For someone to bring in this can of gas we're supposed to pass around after we eat."
A childhood belief about farting

others believed things like this
- I used to think it was an amazing coincidence that all my members of my family had the same name.— Raj
- I used to believe that a 'soul' was an organ of the human body, such as a kidney or lung. — Grace
- I used to think that a gherkin was some kind of piece of machinery. I wonder where I got THAT from...— Some Idiot
- I used to think people were called "human beans".— Dave
- I used to believe the Do Not Pass signs on the roads meant you were'nt aloud to pass the sign. I was 14.Anon
- I used to think that if a lawyer lost his case, he had to go to jail with his client.Anon