Halpernhas retractedan earlier claimthat Cox'sTheoremis deductivelyunsound,but he has renewedand amplifiedhis objectionsto the reasonablenessof the theoremfor finite domains. His newargumenthighlights one functional equationusedbyCoxin 1946but whichis missingin 1978. Thecircumstancesof its disappearanceare explored,along with someof the advancesin knowledgesince 1946which accountfor its absence.