We doubt that John went to the kitchen. It is impossible that Brian is a swan. It is almost certain that Julius is gray. It is likely that if 'Brian is a swan' or 'Julius is gray' or both then Greg is a lion. It is probable that if either 'Brian is a swan' or 'Julius is gray' but not both then Bernhard is a rhino. There is almost no chance that if 'Julius is gray and John went to the kitchen' then Emily is a mouse.
It is probable that 'Brian is a swan and Emily is a mouse'.
It is impossible that 'Brian is a swan and Emily is a mouse'.
It is probable that 'Brian is a swan and Emily is a mouse'.

  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.
  0.0::factB.
  0.95::factC.
  %hop1
  0.7::factX:-or(factB,factC).
  0.7::factY:-xor(factB,factC).
  0.02::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Brian is a swan and Emily is a mouse'.