It is probably not the case that Lily is yellow. It is unlikely that Mary left the football. There is a better than even chance that Julius is a rhino. Chances are slight that if 'Julius is a rhino and Lily is yellow' then John went to the hallway. It is certain that if either 'Mary left the football' or 'Julius is a rhino' but not both then Bernhard is a frog. It is probable that if either 'Mary left the football' or 'Julius is a rhino' but not both then Sandra got the milk.
It is certain that 'Mary left the football' or 'Lily is yellow' or both.
Chances are about even that 'Mary left the football' or 'Lily is yellow' or both.
It is certain that 'Mary left the football' 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
  0.25::factA.
  0.2::factB.
  0.6::factC.
  %hop1
  0.1::factX:-and(factC,factA).
  1.0::factY:-xor(factB,factC).
  0.7::factZ:-xor(factB,factC).

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

  query(conclusion).
  
'Mary left the football' or 'Lily is yellow' or both.