but R. Simeon holds that he has not incurred guilt at all’. But whatever you think is the opinion of R. Simeon [there is always a difficulty]! If he holds that one prohibition can be superimposed upon a pre-existing prohibition, then he should have incurred guilt on account of the nerve too; and if he holds that one prohibition cannot be superimposed upon a pre-existing prohibition, then he should have incurred guilt on account of uncleanness, for that came first; and if he holds that nerves do not impart a flavour, then he should have incurred guilt [at least] on account of the nerve! — Raba answered: In truth he holds that nerves do not impart a flavour, but it is different in that case for the verse says: Therefore the children of Israel eat not the sciatic nerves, that is, the nerve is forbidden but the flesh permitted; this case therefore must be excluded since the nerve would be forbidden and the flesh forbidden too. Rab Judah said in the name of Rab: If a person ate the sciatic nerve of a nebelah he has, according to R. Meir, incurred guilt twice; but the Sages hold that he has incurred guilt once only. The Sages, however, agree with R. Meir that if a person ate the sciatic nerve of a burnt-offering or of an ox that was condemned to be stoned he would have incurred guilt twice. Who is this authority who holds that a comprehensive prohibition alone cannot be superimposed upon an existing prohibition whereas a comprehensive prohibition which also imposes a graver penalty can? — Raba said: It is R. Jose the Galilean. For we have learnt: If a person that was unclean ate either unclean or clean consecrated food, he is liable. R. Jose the Galilean says: If a person that was unclean ate clean consecrated food he is liable, but if he ate unclean consecrated food he is not liable, for he has only eaten what was unclean. They replied to him: Even where he that was unclean ate what was clean, as soon as he touched it he has rendered it unclean! [Now it was asked thereon]: The Rabbis have surely replied well to R. Jose the Galilean? And Raba explained that where the person was rendered unclean and only later the meat was rendered unclean, all agree that he is liable, for the prohibition involving the penalty of kareth came first. They differ only where the meat was first rendered unclean and later the person became unclean. The Rabbis adopt the principle of a comprehensive prohibition, arguing thus: Since he would now be liable for [eating] any piece of [consecrated] food that was clean he is also liable for [eating] a piece that was unclean. R. Jose the Galilean does not adopt the principle of a comprehensive prohibition, for he does not accept the argument ‘since’. But according to R. Jose the Galilean, even though he holds that the comprehensive prohibition which involves only a light penalty cannot [be superimposed upon an existing prohibition], surely the comprehensive prohibition which involves a graver penalty ought to be superimposed upon the prohibition with the light penalty! And what is [the gravity] here? It is in respect of the uncleanness of the person, since it involves the penalty of kareth! — R. Ashi replied: But who shall say that it is in respect of the uncleanness of the person that the gravity lies, perhaps the gravity is in respect of the uncleanness of the meat, since it can never be rendered clean by [immersion in] a mikweh?16ᵃᵇᶜᵈᵉᶠᵍʰⁱʲᵏˡᵐⁿᵒᵖ