When I was six I didn't know about carrying numbers (who does?). I thought that 66 + 66 = 1212 and proceeded to write this and many other incorrect equations on a piece of paper. My dad told me that was wrong but I argued with him about it.
A childhood belief about counting

others believed things like this
- I could NOT understand why, if a pen worked on paper, it couldn't also write in thin air.— Can you guess what it is yet?
- I used to believe fax machines instantly teleported a piece of paper to who ever you wanted. Anon
- I used to believe that numbers had gender, that the odd numbers were boys and even numbers were girls. — Evelyn
- At the age of about 5, I thought that any man carrying a bag/sack over his shoulder was a burglar.— Police officer, Ola.
- When I was 5, I argued with a friend because I thought I never have been 3 years oldAnon
- I used to be terrified of the numbers 18 and 19. I think I thought that when you turned 18 or 19, you die.— Emmy