It is highly likely that Winona is a cat. We believe that Greg is a rhino. It is highly unlikely that Daniel got the football. There is a very good chance that if 'Winona is a cat and Daniel got the football' then Sandra left the milk. It is certain that if either 'Greg is a rhino' or 'Winona is a cat' but not both then Mary discarded the apple. It is probable that if 'Daniel got the football and Greg is a rhino' then Jason is tired.
It is unlikely that either 'Sandra left the milk' or 'Winona is a cat' but not both.
It is highly likely that either 'Sandra left the milk' or 'Winona is a cat' but not both.
It is unlikely that either 'Sandra left the milk' or 'Winona is a cat' but not both.

  and(A,B) :- A,B.
  or(A,B) :- A;B.
  nand(A,B) :- not(and(A,B)).
  nor(A,B) :- not(or(A,B)).
  xor(A,B) :- or(A,B), nand(A,B).

  %hop0
  0.9::factA.
  0.75::factB.
  0.05::factC.
  %hop1
  0.8::factX:-and(factA,factC).
  1.0::factY:-xor(factB,factA).
  0.7::factZ:-and(factC,factB).

  %hop2
  conclusion:-xor(factX,factA).

  query(conclusion).
  
Either 'Sandra left the milk' or 'Winona is a cat' but not both.