Niddah

What does it  exclude?  If it be suggested that it  was intended to exclude the case  where the majority rule is opposed by the rule of presumption  so that in such a case terumah  may not be burnt on its account,  surely [it could be retorted] did not R. Johanan once say this,  for we learnt, 'If a child is found at the side of dough, with a piece of dough in his hand, R. Meir declares the dough clean, but the Sages declare it unclean because it is the nature of a child to slap  [dough]';  and when it was asked, 'What is R. Meir's reason' [the answer given was that] he holds the view that though most children slap dough a minority of them do not, and since this dough stands in the presumption of cleanness;  you combine the status of the minority  with the rule of presumption  and the majority rule  is impaired,  while the Rabbis [regard] the minority as non-existent, and, where the majority rule is opposed by that of presumption, the majority rule takes precedence; and in connection with this Resh Lakish citing R. Oshaia stated: This is a presumption  on the strength of which terumah is burnt,  while R. Johanan stated, This  is not a presumption on the strength of which terumah is burnt?  — It  was rather intended to exclude the rule of majority of which R. Judah spoke.  For we learnt: If a woman aborted a shapeless object,  if there was blood with it she is unclean  otherwise she is clean; R. Judah ruled: In either case she is unclean.  And in connection with this Rab Judah citing Samuel stated: R. Judah declared the woman unclean only where the shapeless object had the colour of one of the four kinds of blood,  but if it had that of any other kinds of blood  the woman is clean, while R. Johanan stated: [If it had the colour] of one of the four kinds of blood  all  agree that she is unclean, and if it had that of any other kinds of blood all agree that she is clean; they  differ only in the case where she aborted something