It is certain that Brian is yellow. We believe that Antoine is hungry. There is a better than even chance that Greg is white. It is almost certain that if either 'Antoine is hungry' or 'Brian is yellow' but not both then Sandra left the milk. We believe that if either 'Greg is white' or 'Antoine is hungry' but not both then Julius is green. We doubt that if 'Greg is white and Brian is yellow' then Mary dropped the apple.
There is almost no chance that 'Antoine is hungry and Greg is white'.
Chances are about even that 'Antoine is hungry and Greg is white'.
There is almost no chance that 'Antoine is hungry and Greg is white'.

  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
  1.0::factA.
  0.75::factB.
  0.6::factC.
  %hop1
  0.95::factX:-xor(factB,factA).
  0.75::factY:-xor(factC,factB).
  0.2::factZ:-and(factC,factA).

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

  query(conclusion).
  
'Antoine is hungry and Greg is white'.