There is almost no chance that John picked up the apple. It is almost certain that Bernhard is a rhino. It is highly unlikely that Lily is white. It is probably the case that if 'Lily is white and John picked up the apple' then Greg is a frog. It is certain that if 'John picked up the apple' or 'Bernhard is a rhino' or both then Julius is a swan. It is probable that if 'Bernhard is a rhino and John picked up the apple' then Yann is bored.
It is almost certain that 'Julius is a swan and Bernhard is a rhino'.
It is almost certain that 'Julius is a swan and Bernhard is a rhino'.
Chances are about even that 'Julius is a swan and Bernhard is a rhino'.

  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
  0.02::factA.
  0.95::factB.
  0.05::factC.
  %hop1
  0.7::factX:-and(factC,factA).
  1.0::factY:-or(factA,factB).
  0.7::factZ:-and(factB,factA).

  %hop2
  conclusion:-and(factY,factB).

  query(conclusion).
  
'Julius is a swan and Bernhard is a rhino'.