We doubt that Julius is gray. There is almost no chance that Sumit is tired. There is almost no chance that Winona is a sheep. There is a very good chance that if 'Winona is a sheep' or 'Julius is gray' or both then Mary went to the kitchen. There is a very good chance that if 'Winona is a sheep' or 'Julius is gray' or both then Lily is a lion. We believe that if 'Julius is gray' or 'Winona is a sheep' or both then Brian is a frog.
It is impossible that 'Winona is a sheep and Julius is gray'.
It is impossible that 'Winona is a sheep and Julius is gray'.
We believe that 'Winona is a sheep and Julius is gray'.

  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
  0.2::factA.
  0.02::factB.
  0.02::factC.
  %hop1
  0.8::factX:-or(factC,factA).
  0.8::factY:-or(factC,factA).
  0.75::factZ:-or(factA,factC).

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

  query(conclusion).
  
'Winona is a sheep and Julius is gray'.