It is likely that Bernhard is a swan. There is a better than even chance that Mary moved to the garden. Chances are slight that Emily is a mouse. Chances are slight that if 'Bernhard is a swan and Mary moved to the garden' then Brian is gray. It is impossible that if either 'Bernhard is a swan' or 'Mary moved to the garden' but not both then Sandra left the apple. There is almost no chance that if either 'Emily is a mouse' or 'Mary moved to the garden' but not both then Julius is a rhino.
It is improbable that 'Emily is a mouse' or 'Bernhard is a swan' or both.
We believe that 'Emily is a mouse' or 'Bernhard is a swan' or both.
It is improbable that 'Emily is a mouse' or 'Bernhard is a swan' 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
  0.7::factA.
  0.6::factB.
  0.1::factC.
  %hop1
  0.1::factX:-and(factA,factB).
  0.0::factY:-xor(factA,factB).
  0.02::factZ:-xor(factC,factB).

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

  query(conclusion).
  
'Emily is a mouse' or 'Bernhard is a swan' or both.