2021/11/5 There was a trick I used to really like. I learned it in elementary school. Not from the school, of course. You stand so that you can barely touch a wall, or other vertical surface, with the tip of your longest finger. Then you let your arm drop to your side and rub it with your other hand. When you put your arm back up “It's shorter!”, you can't reach the wall. Works even when you know the trick and how it operates. The thing I liked, I think, was the almost absolute replicability while not understanding how it could happen. I was looking for something that was off about the world. I wanted proof that things weren't as they seemed, or were as they seemed in opposition to what I'd been told. Any hook on something solid that I could know for real. This trick wasn't it of course, but it had something. It showed that tricks can work, even on people who should be able to avoid being tricked. The replicability of illusions and tricks shows that tricks are fundamental to how we experience the world. That our sensory and interpretation apparata are flawed in predictable ways. That's on the road to an understanding of something real.