It is probable that John got the apple. It is improbable that Brian is a frog. We believe that Lily is green. There is a better than even chance that if either 'John got the apple' or 'Brian is a frog' but not both then Yann is hungry. There is a better than even chance that if either 'John got the apple' or 'Lily is green' but not both then Bill went to the office. Chances are about even that if 'John got the apple' or 'Lily is green' or both then Bernhard is white.
It is highly unlikely that 'Bernhard is white and Lily is green'.
Chances are about even that 'Bernhard is white and Lily is green'.
It is highly unlikely that 'Bernhard is white and Lily is green'.

  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.
  0.1::factB.
  0.75::factC.
  %hop1
  0.6::factX:-xor(factA,factB).
  0.6::factY:-xor(factA,factC).
  0.5::factZ:-or(factA,factC).

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

  query(conclusion).
  
'Bernhard is white and Lily is green'.