It is likely that Bernhard is a swan. It is highly unlikely that Lily is a rhino. It is highly likely that Julius is a swan. It is improbable that if 'Bernhard is a swan' or 'Julius is a swan' or both then Antoine is hungry. There is a very good chance that if 'Bernhard is a swan' or 'Lily is a rhino' or both then Mary dropped the milk. Chances are about even that if either 'Bernhard is a swan' or 'Julius is a swan' but not both then Bill left the football.
It is unlikely that 'Lily is a rhino' or 'Julius is a swan' or both.
It is highly likely that 'Lily is a rhino' or 'Julius is a swan' or both.
It is unlikely that 'Lily is a rhino' or 'Julius 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
  0.7::factA.
  0.05::factB.
  0.9::factC.
  %hop1
  0.1::factX:-or(factA,factC).
  0.8::factY:-or(factA,factB).
  0.5::factZ:-xor(factA,factC).

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

  query(conclusion).
  
'Lily is a rhino' or 'Julius is a swan' or both.