It is likely that Daniel got the milk. It is highly likely that Greg is a swan. It is probably not the case that Mary dropped the apple. It is unlikely that if 'Mary dropped the apple and Daniel got the milk' then Lily is green. There is a very good chance that if either 'Mary dropped the apple' or 'Greg is a swan' but not both then Julius is gray. It is likely that if 'Mary dropped the apple and Daniel got the milk' then John went to the hallway.
It is highly unlikely that 'Lily is green and Mary dropped the apple'.
It is highly unlikely that 'Lily is green and Mary dropped the apple'.
There is a very good chance that 'Lily is green and Mary dropped the apple'.

  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
  0.7::factA.
  0.9::factB.
  0.25::factC.
  %hop1
  0.2::factX:-and(factC,factA).
  0.8::factY:-xor(factC,factB).
  0.7::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Lily is green and Mary dropped the apple'.