We believe that Greg is green. It is impossible that Mary moved to the garden. There is almost no chance that Brian is gray. We doubt that if either 'Mary moved to the garden' or 'Greg is green' but not both then Lily is white. It is probably the case that if either 'Brian is gray' or 'Greg is green' but not both then John left the apple. It is likely that if 'Greg is green and Brian is gray' then Bernhard is a swan.
Chances are about even that 'Greg is green and John left the apple'.
Chances are about even that 'Greg is green and John left the apple'.
There is almost no chance that 'Greg is green and John left 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
  0.75::factA.
  0.0::factB.
  0.02::factC.
  %hop1
  0.2::factX:-xor(factB,factA).
  0.7::factY:-xor(factC,factA).
  0.7::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Greg is green and John left the apple'.