Quote Originally Posted by Sakuraluna View Post
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Well, most likely Alphinaud and Alisaie are in Eorzea illegally. In the Astrologian questline, you find out that leaving Sharlayan is heavily regulated and is in such a way that the brightest minds of Sharlayan are never allowed to leave as they are considered national resources. As such, Alphinaud, who is said to be a child prodigy and benefited from the education of his grandfather, (who himself has been stated to be rather higher up in the hierarchy before his leaving) would very likely be considered one of these national resources and would never be allowed to leave.

No idea where his father, Fourchenault, stands in the contest of Bibliothecs and their opponents. The Bibliothecs, as we are also told in the Astrologian story, are responsible for keeping Sharlayan technology from Eorzeans.