premise: But Schnabel was a great teacher in addition to being a great performer , and the <mask> that four of the ten versions I listened to are by Schnabel pupils ( Clifford Curzon , Frank Glazer , Adrian Aeschbacher , and Victor Babin ) also sheds light on the master 's pedagogical skills .
hypothesis: the proper context for <mask> here should be a statement or assertion of verified information about something that is the case or has happened