i used to believe that any water whatsoever on a boat would make it sink.
A childhood belief about water

others believed things like this
- When I was little, I thought you had to put a finger under the water to make it hot. — M_2
- I used to believe that the last line of Row Row Row Your Boat was 'Life is butter dream'.— Mindless Misfit
- If you eat 30 minutes before swimming, you will sink.Anon
- i used to believe that a monster lived in the garbage disposal. i would never go near the sink— Whitney
- I used to believe all liquids were water-based with things added to it to make different kinds of liquids.Anon
- I thought that hydrogen was pure water (since I knew hydro- meant water) and H2O was impure some how— Hexetic