It is unlikely that Greg is yellow. Chances are slight that Brian is a frog. We believe that John moved to the garden. It is unlikely that if 'John moved to the garden' or 'Greg is yellow' or both then Sandra dropped the milk. We believe that if 'John moved to the garden' or 'Brian is a frog' or both then Mary left the football. We doubt that if 'Greg is yellow' or 'Brian is a frog' or both then Lily is gray.
There is little chance that 'Sandra dropped the milk' or 'Mary left the football' or both.
There is a better than even chance that 'Sandra dropped the milk' or 'Mary left the football' or both.
There is little chance that 'Sandra dropped the milk' or 'Mary left the football' 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
  0.2::factA.
  0.1::factB.
  0.75::factC.
  %hop1
  0.2::factX:-or(factC,factA).
  0.75::factY:-or(factC,factB).
  0.2::factZ:-or(factA,factB).

  %hop2
  conclusion:-or(factX,factY).

  query(conclusion).
  
'Sandra dropped the milk' or 'Mary left the football' or both.