There is almost no chance that Lily is a rhino. It is improbable that Bernhard is white. We doubt that John dropped the apple. It is probably not the case that if 'Lily is a rhino' or 'Bernhard is white' or both then Yann is hungry. It is probable that if 'Lily is a rhino' or 'John dropped the apple' or both then Gertrude is a cat. Chances are about even that if 'Lily is a rhino and Bernhard is white' then Brian is yellow.
Chances are slight that 'Gertrude is a cat and John dropped the apple'.
Chances are slight that 'Gertrude is a cat and John dropped the apple'.
It is probably the case that 'Gertrude is a cat and John dropped the apple'.

  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.
  0.1::factB.
  0.2::factC.
  %hop1
  0.25::factX:-or(factA,factB).
  0.7::factY:-or(factA,factC).
  0.5::factZ:-and(factA,factB).

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

  query(conclusion).
  
'Gertrude is a cat and John dropped the apple'.