Until I was about 9 years old, I periodically considered the possibility that I was the only real person anywhere. The world I lived in was a realistic alien-induced hallucination, and that when I walked anywhere, I actually remained stationary on a sphere (think of a treadmill that goes in all directions). At times, I would suddenly change my behavior, to throw the aliens off track.
This started long before The Matrix, or even Star Trek's holodeck came out. :\
A childhood belief about i'm different

others believed things like this
- I used to believe that the Captain's Log in Star Trek, was really a log— Anna
- I used to believe that the visible rays of the sun were beaming people up to heaven. like in star trek.Anon
- I thought the ball-headed person in the Bic logo was an alien and communicated using alien-like noises.Anon
- i thought aliens would come to earth year 2000 because of a commercial were an alien ate a hot dog— ulle
- I used to believe that I was the only real person in the world and that everyone else were fake things!— supermk342
- I used to believe that every person in the world had a twin, and that I had a long-lost twin in France.— Ashley