There is a better than even chance that Julius is white. It is unlikely that Mary moved to the garden. It is certain that Greg is a swan. It is highly unlikely that if 'Julius is white and Mary moved to the garden' then Jessica is a sheep. It is probable that if 'Mary moved to the garden and Greg is a swan' then Fred dropped the milk. It is unlikely that if 'Greg is a swan and Julius is white' then Sandra left the milk.
Chances are slight that 'Jessica is a sheep' or 'Sandra left the milk' or both.
Chances are slight that 'Jessica is a sheep' or 'Sandra left the milk' or both.
It is almost certain that 'Jessica is a sheep' or 'Sandra left the milk' 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
  0.6::factA.
  0.2::factB.
  1.0::factC.
  %hop1
  0.05::factX:-and(factA,factB).
  0.7::factY:-and(factB,factC).
  0.2::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Jessica is a sheep' or 'Sandra left the milk' or both.