There is a better than even chance that Jessica is a cat. It is impossible that Brian is a frog. It is probable that Mary moved to the office. We believe that if 'Mary moved to the office and Jessica is a cat' then Bernhard is white. It is probably not the case that if 'Brian is a frog' or 'Mary moved to the office' or both then John picked up the apple. It is highly likely that if either 'Mary moved to the office' or 'Brian is a frog' but not both then Lily is a swan.
There is almost no chance that 'Bernhard is white' or 'Jessica is a cat' or both.
There is a better than even chance that 'Bernhard is white' or 'Jessica is a cat' or both.
There is almost no chance that 'Bernhard is white' or 'Jessica is a cat' or 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
  0.6::factA.
  0.0::factB.
  0.7::factC.
  %hop1
  0.75::factX:-and(factC,factA).
  0.25::factY:-or(factB,factC).
  0.9::factZ:-xor(factC,factB).

  %hop2
  conclusion:-or(factX,factA).

  query(conclusion).
  
'Bernhard is white' or 'Jessica is a cat' or both.