What I was 9, I lay awake thinking about how humanity will one day explore space and discover all sorts of new species, make new friends.. I imagined music concerts with humans and animals and all sorts of creatures.. and then it hit me, I won't be alive by then. I basically realized I'm mortal, and cried for hours.
I want that type of sadness back, please. Right now I'm relieved if anything to know I won't see 2126 and beyond, but that's not because I'm inherently pessimistic, I came to this world optimistic as can be.