Whether congenital organ absence (chaseir) renders an animal treif

Description

The Chasam Sofer redefines chaseir as 'absent from the beginning of the relevant legal context' rather than absolutely congenital, resolving tensions between the Rambam and Rashba and between treifos and tumah terminology. He rules that land fowl with congenital skull holes are permitted by the letter of the law, while waterfowl with such defects are treif because their soft brain membrane will inevitably be damaged without bony protection.