June 28, 2003 - Tetsuya Takahashi Xenosaga Interview
http://web.archive.org/web/20030814044553/http://www.playstation.jp/psstyle/talk/02/02.html
--Why did you choose space as the setting? Were you not interested in a fantasy world?
Xenogears started out as a sequel to "Chrono Trigger. However, as we went through various meetings with the publishers, we began to realize that there were some practical difficulties. We went to the trouble of asking Mr. Sakaguchi to make it an original title. However, since development had already started, there were parts of the game where I couldn't go back to the fantasy world, and I was concerned about the motivation of the staff. To some extent, we made a compromise, and the result was Xenogears."
――なぜ舞台を宇宙にしたのですか。ファンタジーの世界には興味がなかった?
「『ゼノギアス』は、そもそも最初は『クロノトリガー』の続編を作るところからスタートしていたんです。ただ、出版社の方たちといろいろな打ち合わせを重ねているうちに、現実的に難しい部分がでてきて……。わざわざ坂口さんに骨を折ってもらい、オリジナルタイトルにしてもらったんです。ただ、開発はスタートしていたので、ファンタジーの世界に戻れない部分もあったし、スタッフのモチベーションも気になったし。ある程度、折衷して作ったのが『ゼノギアス』だったんです。」
From: Interviews