It is highly likely that Jessica is a mouse. It is impossible that Bernhard is yellow. It is unlikely that Fred dropped the milk. Chances are slight that if 'Fred dropped the milk' or 'Bernhard is yellow' or both then Mary left the football. There is almost no chance that if 'Bernhard is yellow and Fred dropped the milk' then Lily is a lion. It is probable that if 'Fred dropped the milk and Jessica is a mouse' then Brian is a frog.
There is almost no chance that 'Mary left the football' or 'Lily is a lion' or both.
There is almost no chance that 'Mary left the football' or 'Lily is a lion' or both.
It is highly likely that 'Mary left the football' or 'Lily is a lion' 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
  0.9::factA.
  0.0::factB.
  0.2::factC.
  %hop1
  0.1::factX:-or(factC,factB).
  0.02::factY:-and(factB,factC).
  0.7::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Mary left the football' or 'Lily is a lion' or both.