It’s amusing for me to think which came first: Did I believe something exists because I could see it, smell it, or feel it, etc? Or did something come to exist because I believed it first? Our protagonist, Tim in the blue jeans, sees a bridge and an icecream, but needs to tell his friend they are invisible because there is no other way to explain why his friend cannot see them.
Would you know if you were insane? Maybe 1111 is something you created for yourself?