It is highly unlikely that Greg is green. It is unlikely that Jessica is a mouse. It is improbable that Lily is a rhino. It is likely that if either 'Jessica is a mouse' or 'Lily is a rhino' but not both then Sandra got the football. Chances are about even that if either 'Greg is green' or 'Jessica is a mouse' but not both then Mary dropped the milk. It is likely that if either 'Jessica is a mouse' or 'Lily is a rhino' but not both then Brian is a frog.
It is almost certain that either 'Jessica is a mouse' or 'Brian is a frog' but not both.
It is improbable that either 'Jessica is a mouse' or 'Brian is a frog' but not both.
It is almost certain that either 'Jessica is a mouse' or 'Brian is a frog' 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
  0.05::factA.
  0.2::factB.
  0.1::factC.
  %hop1
  0.7::factX:-xor(factB,factC).
  0.5::factY:-xor(factA,factB).
  0.7::factZ:-xor(factB,factC).

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

  query(conclusion).
  
Either 'Jessica is a mouse' or 'Brian is a frog' but not both.