There is little chance that Daniel left the apple. Chances are slight that John grabbed the milk. It is improbable that Bernhard is a swan. It is certain that if either 'John grabbed the milk' or 'Daniel left the apple' but not both then Brian is a lion. It is unlikely that if either 'Bernhard is a swan' or 'John grabbed the milk' but not both then Julius is a rhino. There is a very good chance that if 'John grabbed the milk and Bernhard is a swan' then Lily is a frog.
It is highly likely that 'Lily is a frog' or 'Bernhard is a swan' or both.
There is little chance that 'Lily is a frog' or 'Bernhard is a swan' or both.
It is highly likely that 'Lily is a frog' or 'Bernhard is a swan' 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
  0.1::factA.
  0.1::factB.
  0.1::factC.
  %hop1
  1.0::factX:-xor(factB,factA).
  0.2::factY:-xor(factC,factB).
  0.8::factZ:-and(factB,factC).

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

  query(conclusion).
  
'Lily is a frog' or 'Bernhard is a swan' or both.