There is a better than even chance that Julius is a swan. It is unlikely that Mary moved to the garden. Chances are slight that Winona is a sheep. It is probable that if 'Winona is a sheep' or 'Mary moved to the garden' or both then Antoine is thirsty. It is probably not the case that if either 'Julius is a swan' or 'Mary moved to the garden' but not both then Brian is a swan. It is impossible that if 'Winona is a sheep and Julius is a swan' then Bill went to the bedroom.
There is almost no chance that 'Brian is a swan and Antoine is thirsty'.
There is almost no chance that 'Brian is a swan and Antoine is thirsty'.
There is a better than even chance that 'Brian is a swan and Antoine is thirsty'.

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

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

  query(conclusion).
  
'Brian is a swan and Antoine is thirsty'.