Chances are about even that Mary got the football. We believe that Jessica is a cat. It is highly likely that Brian is yellow. It is certain that if either 'Brian is yellow' or 'Jessica is a cat' but not both then John went to the kitchen. It is probably the case that if 'Jessica is a cat and Mary got the football' then Bernhard is a frog. We doubt that if 'Mary got the football and Brian is yellow' then Greg is yellow.
It is highly likely that 'Jessica is a cat' or 'Mary got the football' or both.
It is highly likely that 'Jessica is a cat' or 'Mary got the football' or both.
It is unlikely that 'Jessica is a cat' or 'Mary got the football' 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
  0.5::factA.
  0.75::factB.
  0.9::factC.
  %hop1
  1.0::factX:-xor(factC,factB).
  0.7::factY:-and(factB,factA).
  0.2::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Jessica is a cat' or 'Mary got the football' or both.