We believe that Mary discarded the apple. It is probably not the case that Brian is white. We believe that Greg is a frog. There is a better than even chance that if either 'Brian is white' or 'Mary discarded the apple' but not both then John went to the hallway. It is likely that if 'Brian is white and Greg is a frog' then Lily is a lion. Chances are slight that if either 'Mary discarded the apple' or 'Brian is white' but not both then Julius is yellow.
Chances are slight that 'Lily is a lion and Greg is a frog'.
Chances are slight that 'Lily is a lion and Greg is a frog'.
It is likely that 'Lily is a lion and Greg is a frog'.

  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.
  0.25::factB.
  0.75::factC.
  %hop1
  0.6::factX:-xor(factB,factA).
  0.7::factY:-and(factB,factC).
  0.1::factZ:-xor(factA,factB).

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

  query(conclusion).
  
'Lily is a lion and Greg is a frog'.