Niddah

But according to him who taught  the first explanation  [it may be objected:] Was it not in fact taught, in agreement with the latter version, that the reason is to avoid the neglect of propagation? It is this that Hillel in fact said to Shammai, 'Even if you give as your reason that "if in fact any blood were there it would have flowed out earlier," you must nevertheless make a fence  for your ruling, for why should this law be different from all the Torah for which a fence is made?' To this the other replied, 'If so,  you would cause the daughters of Israel to neglect marital life'.  And Hillel?  — 'Do I [he can reply] speak of marital life?  I only speak of levitical cleanness'. And Shammai?  — [Restrictions, he holds, must] not [be imposed] even as regards levitical cleanness, since otherwise  the man might have scruples  and keep away altogether. (Mnemonic:  Bottom examined covered in a corner.) It was stated: If one corner of a basket was used for levitically clean objects and a dead creeping thing was found in another corner, Hezekiah ruled that the objects that were formerly  clean remain clean. R. Johanan ruled: The objects that were formerly  clean are now regarded as retrospectively unclean. But do not Shammai  and Hillel in fact agree  in the case of a basket that the objects that were formerly clean are deemed to be retrospectively unclean?  — Shammai and Hillel agree  only in the case of a basket that had a bottom,  while Hezekiah and R. Johanan differ in that of a basket that had no bottom.  But if the basket had no bottom what could be R. Johanan's reason?  — It had no bottom, but it had  a rim.  But surely, it was taught:  'If a man drew  ten buckets of water one after the other  and a creeping thing was found in one of them, this one  is unclean and all the others  remain clean';  and in connection with this Resh Lakish citing R. Jannai stated, 'This  was taught only in a case where the bucket had no rim  but if it had a rim  all the buckets of water are deemed to be unclean.' Now must it be assumed that Hezekiah  does not adopt the view of R. Jannai?  — [No, since] water  glides  while fruits  do not glide;  or else [it may be replied] one is not particular with water  but with fruit one is particular.  And if you prefer I might reply: Shammai and Hillel agree  only in respect of a basket that was not [previously]  examined