Some additional considerations for Galactic lifespans.
I'm unclear on details as this comes from a set of light novels that have not yet been translated into English, but Mihoshi's Grandfather and Great-Aunt are apparently competitive with Seto on how old they are. As a prominant family in the galaxy this may be due to having the best medical tech available even if they don't have the effective eternal youth that seems to come with a royal tree. Likewise, the character of Neju Na Melmas from GXP was high priestess/head of state for the planet Melmas and was artificially kept at a physical age of 10 for about 2000 years.
I don't know if you are going with the canon date of 1000 years ago or the more commonly accpted fannon of 10000 years for the Moon Kingdom, but yes, Seto was probably around at even the longer of those two dates, Washu certainly was, and records should exist unless the Moon Kingdom was totally isolationist. I sometimes wonder about possible connections between Seto and Setsuna. (Both 10,000 years old, green hair, red eyes, tendency to meddle...)
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No, I don't believe the world has gone mad. In order for it to go mad it would need to have been sane at some point.
I'm unclear on details as this comes from a set of light novels that have not yet been translated into English, but Mihoshi's Grandfather and Great-Aunt are apparently competitive with Seto on how old they are. As a prominant family in the galaxy this may be due to having the best medical tech available even if they don't have the effective eternal youth that seems to come with a royal tree. Likewise, the character of Neju Na Melmas from GXP was high priestess/head of state for the planet Melmas and was artificially kept at a physical age of 10 for about 2000 years.
I don't know if you are going with the canon date of 1000 years ago or the more commonly accpted fannon of 10000 years for the Moon Kingdom, but yes, Seto was probably around at even the longer of those two dates, Washu certainly was, and records should exist unless the Moon Kingdom was totally isolationist. I sometimes wonder about possible connections between Seto and Setsuna. (Both 10,000 years old, green hair, red eyes, tendency to meddle...)
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No, I don't believe the world has gone mad. In order for it to go mad it would need to have been sane at some point.