It is necessary that if someone wants to arrive at the truth on some disputed question that he try to defend each of the opposing theories as far as this is possible. Then the absurdity of the view he [wishes] to refute will be more easily established. For if he refutes any one of these theories but does not first try to argue for it (as far as possible), his refutation of that view is not well-grounded. This is obvious.
[Levi ben Gershom, The Wars of the Lord, Volume One, Feldman, tr. Jewish Publication Society of America (Philadelphia: 1984) p. 119.]
Thanks to Amazon gift cards for Christmas, I was able to attain the full three volumes of Feldman's translation of Gersonides's The Wars of the Lord without killing my wallet, which makes me very, very happy. Gersonides, of course, is one of the great medieval Jewish philosophers, and The Wars of the Lord is his major work.