The Gemarah in Chulin (69a) says that milk from a Ben Pekuah (a calf that was in his mother when she was Shechted, which permits it to be eaten from the Torah without Shechita) that stuck out its leg before the Shchitah of the mother (that prohibits the leg) is a question if it could be dranked. Since the milk gets its substanence from all the limbs including the prohibitted one, so it becomes prohibited. The Poskim forbid it, since the question wasn't resolved.

Why should we say it's prohibbited? We have a rule that if two things cause something to be in existance, one is permitted and one prohibbited, the product is permitted. (Zeh V'Zeh Gorem) So the milk which is a by product of permitted and prohibited limbs, why should it prohibit?

We can anwer, in my humble opinion, that when a product of a Heter and Issur (let say a calf which one parent was Ussur)the whole calf is one entity. So this entity is a combination of Isuur and Heter, since this entity is not a product of comlete Isuur its permitted.

But by milk, each molecule is a seperate entity. Therefore, when the limbs give substence to the milk, each particle is getting it from a different limb, which creates it independently. thus we now have a mixture of permitted and prohibited milk, so therefore its Ussur.

We can further ask, if the limb that went out of the womb of her mother is less than 1\60th of the rest of the animal, why isn't it permitted to drink the milk? wouldn't the milk created by the Ussur limb be Butel in the milk created by the permitted limbs?

We can answer, that the Mordichai says, anything that is in a mixture when it was created cannot be Butel. Since all the milk comes out together, it's not Butel.

Ben Pekuach

Now if I mate two beni pekuachs, I can get a herd of ben pekuachs. This is no problem for modern vet med. The objection is that the cows could escape and mate with a regular cow and then we would have half a ben pekuach which means we can't do anything with it as it only has one siman. However, we could insert a lethal gene so the animals are sterile and insert a marker gene like yellow eyes so they could not get lost. Although we would still have to slaughter the offspring for marit eyan we could be more lenient in judging treifot which is of economic value as the majority of the treifot are just chumrahs. Afterall most the of the dairy cattle slaughtered are treifed (personal observation) so the milk would be treif if the cows were really treif.

Milk is made in the mammary gland. The molecules come from blood stream but I don't see how milk is different that it would be unique from any other bitul b'shishim and would be less than zeh vzeh gorem if we consider the reality that every cell in the body comes from both the mother and father. (Chazal express themselves that the white tissues come from the mother and the red tissues from the father.)


Aryeh Shore

quote:

Milk is made in the mammary gland. The molecules come from blood stream but I don't see how milk is different that it would be unique from any other bitul b'shishim and would be less than zeh vzeh gorem if we consider the reality that every cell in the body comes from both the mother and father. (Chazal express themselves that the white tissues come from the mother and the red tissues from the father.)

The reason it wouldn't be Butel is because it was released to the world that way. The Mordichai learns this from that the spitting of blood is a valid spitting by Chalitzah, since there must be some spit mixed in (and we don't say it's Butel.) The same by Shichvas Zerah of a Zav is tameh like Zivah since it's imposssible that a little bit of Ziva is mixed in (And we don't say it's Butel)

My half of Ben Pekuah is different than what you're calling half a Ben pekuah. Mine is that only part of the animal was inside the animal while you're reffering to the "half breed."

As far I know bitul bshishim is only with food. Everything else would be bitul brabim. This applies to something with a shiur of more than mashihu. Since no amount of spit is desinated then a mashiuh is enough.
We learn bitul bshishim from the leg of the Nizir sacrifice. I don't see how the leg of a ben pekuach would be different.

Actually this reminds of the the siyif on salt which is contaminating with blood or spice which which has been contaminated with nevelah fat. Most rishnom say the amount of the issur can not be greater than the issur itself, i.e, we treat the spice as bitul bshishim not as notan taam.

Aryeh Shore

But wouldn't the spittle be considered Butal B'rov? Since there is more blood, then, the whole mixture should be considered blood and the spittle should be Butal and considered non existent. SO you wouldn't have even a Mashahu of spit, since it's Butal.

Perhaps the key to understanding the halakhah is not chemistry but psychology.

IOW, it's not about how things really are, but perceivable reality -- how the world impacts people. After all, isn't the point of halakhah to help one build an attachment to the Creator and perfect the self into an "image" of Him? How would details that are entirely impeceivable change that?

The Mordechai asks why the spit is not bitul in the blood of the chaluza. The torah tmimah suggests that no spit is necessary as spit is not makaiv. Therefore just the act of spitting is sufficient. This would also explain why blood from the mouth of the zav is not tameh, and, presumably blood which is flowing from the mouth of the chaluza is not valid, because just blood is not metameh. So the proof suggested for why the milk from the ben pekuah with a pasul limb is tameh whould make the problem even worse, how come blood from the mouth of the zav is not metameh (nidah נ"ו ) if it is systemic.

Aryeh Shore

“The Mordechai asks why the spit is not bitul in the blood of the chaluza. The torah tmimah suggests that no spit is necessary as spit is not makaiv. Therefore just the act of spitting is sufficient.”

This is itself the Machlokes in the GemarahYevomos 105a if the reason why it’s A Kosher spitting is because it doesn’t say you must spit “spit” it says to spit, so you can spit blood. The other says the reason is because it’s impossible to have blood without having some spit in it (but implies without spit, it’s impossible to “spit” blood, because that wouldn’t be an acyion of “spitting”

The Mordichai’s proof is from the second opinion. The TT seems to explain the first opinion, so it’s not an argument between them.