Chances are slight that Greg is a swan. It is highly likely that Antoine is bored. It is almost certain that Lily is green. Chances are about even that if 'Lily is green and Greg is a swan' then Brian is a rhino. It is impossible that if 'Greg is a swan' or 'Lily is green' or both then Julius is a lion. It is impossible that if 'Antoine is bored and Greg is a swan' then John got the milk.
Chances are slight that either 'Antoine is bored' or 'Greg is a swan' but not both.
There is a very good chance that either 'Antoine is bored' or 'Greg is a swan' but not both.
Chances are slight that either 'Antoine is bored' or 'Greg is a swan' 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.
  0.9::factB.
  0.95::factC.
  %hop1
  0.5::factX:-and(factC,factA).
  0.0::factY:-or(factA,factC).
  0.0::factZ:-and(factB,factA).

  %hop2
  conclusion:-xor(factB,factA).

  query(conclusion).
  
Either 'Antoine is bored' or 'Greg is a swan' but not both.