Niddah

[To turn to] the main text, 'If some earth fell into a ladleful of corpse-mould [the latter remains] unclean, but R. Simeon holds it to be clean. If a ladleful of corpse-mould was scattered in a house the house is unclean,  but R. Simeon holds it to be clean'.  And both these rulings were required. For if we had been informed of the first one only  it might have been presumed that only in that case do the Rabbis maintain their view,  since it  is collected together but that where it was scattered they agree with R. Simeon, since a succession of incomplete overshadowings  is of no consequence.  And if we had been informed of the latter only  it might have been presumed that only in that case does R. Simeon maintain his view,  since a succession of incomplete overshadowings  is of no consequence,  but that in the former case  he agrees with the Rabbis.  Hence both were required. Elsewhere we learnt:  A ladleful and more of the earth of a graveyard  is unclean,  but R. Simeon regards it as clean.  What is the reason of the Rabbis? — Because it is impossible to have 'a ladleful  and more' of the earth of a graveyard in which there is not contained a ladleful of corpse-mould. Now that you have explained that R. Simeon's reason is because 'its final stage is treated as its first stage',  what could be his reason in the case of a PLACENTA?  — R. Johanan replied: Because the law of neutralization in the larger quantity  has been applied to it.  R. Johanan in fact follows here  a view he expressed elsewhere. For R. Johanan stated: R. Simeon and R. Eliezer b. Jacob laid down the same ruling.  R. Simeon laid down the ruling we have just spoken of.  R. Eliezer [also laid down the same ruling] for we learnt:  R. Eliezer b. Jacob ruled, If a beast  of the class of large cattle discharged a clot of blood, this  shall be buried  and [the beast] is exempt from the law of the firstling;  and in connection with this R. Hiyya taught: It  does not convey uncleanness either through touch or through carriage.  But since it conveys no uncleanness either through touch or through carriage  why  should it be buried? — In order to publish the fact that [the beast] is exempt from the law of the firstling. It thus clearly follows that it  is deemed to be a proper embryo,  then why did R. Hiyya teach, 'It does not convey uncleanness either through touch or through carriage'? — R. Johanan replied: Because the law of neutralization in the larger quantity  has been applied to it. R. Ammi citing R. Johanan stated: R. Simeon, however,  agrees that its mother is unclean by reason of childbirth. Said a certain old man to R. Ammi: 'I will explain to you R. Johanan's reason:  For Scripture says, If a woman conceived seed  and bore a man-child etc.,  which implies: Even if she bore in the same manner only as she 'conceived seed'  she is unclean by reason of childbirth. Resh Lakish ruled: A sac that was beaten up in its fluid assumes the same status as a corpse whose shape was destroyed.  Said R. Johanan to Resh Lakish: Whence do we infer that a corpse whose shape had been destroyed is clean? If it be suggested, From the following statement which R. Shabthai cited in the name of R. Isaac of Magdala or, as others say, R. Isaac of Magdala cited in the name of R. Shabthai, 'If a corpse has been burnt but its shape remained  it is unclean. It once happened that on account of such a corpse  the big  doors  were declared unclean