It is probably not the case that Lily is gray. It is impossible that Bernhard is white. There is almost no chance that Yann is bored. It is improbable that if 'Yann is bored and Bernhard is white' then Jessica is a sheep. We believe that if 'Lily is gray' or 'Yann is bored' or both then Mary went to the kitchen. It is certain that if 'Yann is bored' or 'Bernhard is white' or both then Brian is yellow.
It is probably not the case that 'Jessica is a sheep' or 'Lily is gray' or both.
It is probably not the case that 'Jessica is a sheep' or 'Lily is gray' or both.
We believe that 'Jessica is a sheep' or 'Lily is gray' 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
  0.25::factA.
  0.0::factB.
  0.02::factC.
  %hop1
  0.1::factX:-and(factC,factB).
  0.75::factY:-or(factA,factC).
  1.0::factZ:-or(factC,factB).

  %hop2
  conclusion:-or(factX,factA).

  query(conclusion).
  
'Jessica is a sheep' or 'Lily is gray' or both.