Tenchi Muyo is one of those series where they put out a lot of supplementary material providing background information you don't see in the anime itself. This material is, of course, in Japanese and non-Japanese-speaking fans have to rely on translations provided by other fans. This information then spreads by word of mouth, web-link, and occasional inclusion into fanfic. This stuff is subject to translation errors, misunderstandings, confusion with fanon, arguments about whether it's proper canon if it's not on screen, etc. For a source I find to be mostly reliable, check out AstroNerdBoy's timeline and linked pages. The afore mentioned timeline has an entry about the Juraian pirates contacting Tsunami long ago.
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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.
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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.