How To Be a Cannibal

The Ramban (11:3) cites the Rambam that the words אותה תאכלו comes to exclude human flesh is prohibited because of an aseh.  The Ramban disagrees since the Gemorah (Ketubos 60b and Kiresos 21b) excludes blood and milk from any issur and the rule is what comes from something that’s tamah is tamah so it must be that the flesh of humans isn’t prohibited.  The Ramban echoes his words in Ketubos 60b.  The Ramban does mention that after death the dead person is assur be’hanah and therefore it will be prohibited.  The Rosh in Ketubos and the Rashba in responsa 364 maintain that human flesh is only rabbinically prohibited (the Meiri and Avnei Nazer Even Ha’ezer 332 indicate the Rambam will also agree to the rabbinic prohibition.)

 In response to the question of the Ramban, the Maggid Mishnah (Maacolos Assuros 2:3) says that according to the Ramban the possuk tells us that the blood and milk are muttar despite the fact that the flesh is assur.  As to why this is understood as an exemption to the rule and doesn’t disproof the rule, the Maggid explains that the rule of something coming from an issur is assur doesn’t apply to an issur aseh (see Shach 79:4 and Pri Migadim ad loc.)  Why should this be true, what’s the difference?  I would suggest that an issur aseh is merely an issur gavreh and doesn’t define the object as a davar tameh.  The Maggid in fact finds it difficult according to the other Rishonim why do you need a possuk to permit the blood and milk.  Rav Chaim on Shas explains the there are two issurim included in coming from something tamah.  1. It’s a siman that what comes from the davar tamah is also assur.  2. It creates a separate issur on what comes from the davar tamah.  The possuk excludes that it doesn’t become its own issur however the Rishinim are assuming that it still should be assur because it came from something tamah.  He explains the Rambam holds both are excluded (he explains it depends on 2 peshatim in Rashi Kiresos.)

The Re’ah is of the opinion that there is an issur lav on human flesh.  He holds that blood should have been included in the issur of basar, however the verse permits it (see Rivash response 373 and the Kehilas Yaakov Zevachim siman 20 for a discussion if blood is considered flesh, the Re’ah holds it is.)      

The Ritvah in Ketubos says that anyway human flesh would be prohibited to eat because of aver min hachai.  The Rashbash responsa 518 maintains this way as well.  The Ran and Rashba (ibid) refute that if it was permitted there would be no obligation of shechitah and hence no aver min hachai (see siman 13 in Bais Yosef and Remah no aver min hachai on fish that don’t require shechitah.)  See also Or Sameach Maacolos Assuros (2:3.)  They seem to be debating if it doesn’t say the din of shechitah do we assume it exists automatically or not.