I got an eyemask for sleeping recently, one of the ones that have the sort of cups since the flat ones feel weird on my eyes. and a weird thing that I never would have considered being a problem and yet nonetheless somehow is, is that I get really dry eyes when I wear them sometimes, and it turns out it's because I just forget to actually close my eyes since it's already so dark. it's so strange how doing anything to augment the human body and subvert it's limitations can have the oddest consequences you never would have expected.
