It is highly unlikely that Bernhard is a lion. It is highly unlikely that Lily is a frog. There is almost no chance that Brian is yellow. It is likely that if 'Brian is yellow and Bernhard is a lion' then Jessica is a cat. It is probable that if either 'Lily is a frog' or 'Brian is yellow' but not both then Greg is a swan. It is almost certain that if 'Lily is a frog' or 'Brian is yellow' or both then John discarded the apple.
There is almost no chance that either 'Brian is yellow' or 'Jessica is a cat' but not both.
There is almost no chance that either 'Brian is yellow' or 'Jessica is a cat' but not both.
It is likely that either 'Brian is yellow' or 'Jessica is a cat' 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.
  0.05::factB.
  0.02::factC.
  %hop1
  0.7::factX:-and(factC,factA).
  0.7::factY:-xor(factB,factC).
  0.95::factZ:-or(factB,factC).

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

  query(conclusion).
  
Either 'Brian is yellow' or 'Jessica is a cat' but not both.