It is improbable that Sandra grabbed the apple. We doubt that Brian is a rhino. It is probable that Mary went to the office. It is certain that if 'Sandra grabbed the apple and Mary went to the office' then Greg is a lion. We believe that if either 'Mary went to the office' or 'Brian is a rhino' but not both then Lily is green. It is impossible that if 'Mary went to the office' or 'Sandra grabbed the apple' or both then Julius is gray.
It is almost certain that either 'Lily is green' or 'Greg is a lion' but not both.
Chances are about even that either 'Lily is green' or 'Greg is a lion' but not both.
It is almost certain that either 'Lily is green' or 'Greg is a lion' but not 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
  0.1::factA.
  0.2::factB.
  0.7::factC.
  %hop1
  1.0::factX:-and(factA,factC).
  0.75::factY:-xor(factC,factB).
  0.0::factZ:-or(factC,factA).

  %hop2
  conclusion:-xor(factY,factX).

  query(conclusion).
  
Either 'Lily is green' or 'Greg is a lion' but not both.