Chances are about even that Lily is yellow. It is certain that Bernhard is a swan. There is almost no chance that Mary went to the office. It is highly unlikely that if 'Bernhard is a swan and Lily is yellow' then Daniel grabbed the apple. It is probably the case that if either 'Bernhard is a swan' or 'Lily is yellow' but not both then Brian is a lion. It is probably not the case that if 'Mary went to the office' or 'Lily is yellow' or both then Winona is a sheep.
There is a very good chance that 'Brian is a lion' or 'Lily is yellow' or both.
There is a very good chance that 'Brian is a lion' or 'Lily is yellow' or both.
It is highly unlikely that 'Brian is a lion' or 'Lily is yellow' 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.
  1.0::factB.
  0.02::factC.
  %hop1
  0.05::factX:-and(factB,factA).
  0.7::factY:-xor(factB,factA).
  0.25::factZ:-or(factC,factA).

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

  query(conclusion).
  
'Brian is a lion' or 'Lily is yellow' or both.