We believe that Winona is a cat. It is probable that Mary went to the kitchen. It is highly likely that Jeff dropped the apple. It is improbable that if 'Jeff dropped the apple' or 'Winona is a cat' or both then Sandra left the football. It is likely that if 'Jeff dropped the apple' or 'Winona is a cat' or both then Lily is yellow. It is almost certain that if either 'Winona is a cat' or 'Mary went to the kitchen' but not both then Greg is yellow.
It is almost certain that 'Greg is yellow' or 'Jeff dropped the apple' or both.
It is almost certain that 'Greg is yellow' or 'Jeff dropped the apple' or both.
It is improbable that 'Greg is yellow' or 'Jeff dropped the apple' or 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
  0.75::factA.
  0.7::factB.
  0.9::factC.
  %hop1
  0.1::factX:-or(factC,factA).
  0.7::factY:-or(factC,factA).
  0.95::factZ:-xor(factA,factB).

  %hop2
  conclusion:-or(factZ,factC).

  query(conclusion).
  
'Greg is yellow' or 'Jeff dropped the apple' or both.