--- title: Black and White World date: 2023-10-16T02:18:50+09:00 --- I don't know how long I've been using a cell phone, but I didn't realize it existed until now. I don't usually try to break my bad habit of looking at my phone in bed before I go to sleep, but a few days ago I noticed a so-called "easy viewing mode" in my phone's preferences window. It's supposed to reduce eye strain by adjusting the blue light on the screen, but when I went to the settings screen, I realized that there was a button that not only adjusted the blue light filter value, but also made the phone screen black and white. I tried it, and it actually made the phone screen black and white. It's not a very useful feature, but I felt like I was going back to the old days before smartphones, so I was glad to see it, and since then, I've been switching to black and white whenever I have time.  But then something strange happened. I'm sure the world is full of colors and only the palm-sized screen of my phone looks black and white, but when I switch to a black and white screen and look at my phone, the world outside my phone suddenly turns black and white as well. I wonder if I'm looking at the wrong thing, so I switch back and forth between my phone screen and the world around me, and the same thing happens. For a moment, the whole world turns black and white. Of course, if you look away from your phone screen, the world fills up with color again, but if you stare at your phone for a while, the world outside becomes black and white as well. I was curious and made some observations, and it turns out that the world doesn't turn black and white at first, but after a certain amount of time spent staring at your phone, the world around you seems to gradually drain away from your phone screen. It's not like there's an exact boundary, but the black and white world pushes out the color and gradually expands its territory around you, like ink smearing on a drawing paper. I find this phenomenon interesting, but at the same time, I wonder if this phenomenon or sensory confusion must mean that my eyes are not responding properly to the outside world, and that the act of looking at a black and white screen to relieve eye strain is actually adding to the strain. "Is this the right thing to do..." I don't know if it's something that happens with age, or if it can happen to anyone. Anyway, out of curiosity, I experimented with it a few times, but the bottom line is that I don't feel like my eyes are getting any healthier, so I'm not sure if it's worth it to keep looking at this black and white screen. Even if you can do it for fun once or twice, the marginal benefit is too obvious to make it a sustainable pastime, and I think it's time to stop. After all, wouldn't it be better if people didn't look at their phones...?