How should Muslim’s Hishām-from-ʿUrwah illustration be understood?

The Meeting Condition in Muʿanʿan Hadith: Muslim’s Rejoinder and Route Comparison

• Muslim proves tadlīs by Hishām in the cited report
• An ʿUthmān intermediary is required in every report
• The specific chain is conclusively ruled disconnected
• Individual reports can be mediated even when the general teacher–student hearing is well established