We believe that Jeff moved to the office. It is highly likely that Brian is a lion. It is improbable that Jessica is a mouse. Chances are slight that if 'Jessica is a mouse' or 'Brian is a lion' or both then John discarded the apple. It is likely that if 'Jessica is a mouse and Brian is a lion' then Greg is yellow. It is unlikely that if 'Jeff moved to the office and Jessica is a mouse' then Bernhard is a rhino.
It is unlikely that 'Brian is a lion' or 'Bernhard is a rhino' or both.
It is highly likely that 'Brian is a lion' or 'Bernhard is a rhino' or both.
It is unlikely that 'Brian is a lion' or 'Bernhard is a rhino' 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
  0.75::factA.
  0.9::factB.
  0.1::factC.
  %hop1
  0.1::factX:-or(factC,factB).
  0.7::factY:-and(factC,factB).
  0.2::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Brian is a lion' or 'Bernhard is a rhino' or both.