There are studies showing that short sightedness is caused by focusing on close objects for extended periods of time. They’ve done numerous studies over decades on the increasing cause of it in children and it essentially boils down to the fact that the eye (when viewing close objects) can’t “unblur” the background (everything that is right behind the close thing you’re looking at). Your eye continues to try to do so. This continual struggle actually reshapes your eye, causing myopia, so your eye literally becomes egg shaped. Notably, the rates drastically increased when kids started doing more “near work” (homework) and spending less time outside.
Before the invention of books, short sightedness was far less common. So let’s blame Gutenberg.
you can’t possibly know that
There are studies showing that short sightedness is caused by focusing on close objects for extended periods of time. They’ve done numerous studies over decades on the increasing cause of it in children and it essentially boils down to the fact that the eye (when viewing close objects) can’t “unblur” the background (everything that is right behind the close thing you’re looking at). Your eye continues to try to do so. This continual struggle actually reshapes your eye, causing myopia, so your eye literally becomes egg shaped. Notably, the rates drastically increased when kids started doing more “near work” (homework) and spending less time outside.
So yes, we do know that.
Here’s a transcript of a podcast that discusses it, with linked citations at the parts it’s discussed at. https://docs.google.com/document/d/e/2PACX-1vRMWnsM8thCF5giSiABkfCFUCxLzjM8PSby1V1Etn4jTavVpcuAwR0wjVhpZ2gLYK3QJUNzRYoiU9_p/pub
It’s not fair!