There is a better than even chance that Brian is white. Chances are about even that Mary moved to the office. It is highly unlikely that John went to the hallway. It is almost certain that if 'John went to the hallway and Mary moved to the office' then Gertrude is a cat. We doubt that if either 'John went to the hallway' or 'Mary moved to the office' but not both then Lily is gray. It is likely that if either 'Mary moved to the office' or 'Brian is white' but not both then Julius is a frog.
There is a better than even chance that 'Lily is gray' or 'Brian is white' or both.
There is a better than even chance that 'Lily is gray' or 'Brian is white' or both.
There is almost no chance that 'Lily is gray' or 'Brian is white' 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
  0.6::factA.
  0.5::factB.
  0.05::factC.
  %hop1
  0.95::factX:-and(factC,factB).
  0.2::factY:-xor(factC,factB).
  0.7::factZ:-xor(factB,factA).

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

  query(conclusion).
  
'Lily is gray' or 'Brian is white' or both.