There is a very good chance that Bill went to the bedroom. It is impossible that Lily is yellow. It is probably the case that John left the football. There is a very good chance that if 'Bill went to the bedroom' or 'Lily is yellow' or both then Bernhard is green. We doubt that if 'Bill went to the bedroom' or 'Lily is yellow' or both then Winona is a wolf. It is impossible that if 'Bill went to the bedroom and John left the football' then Brian is white.
It is almost certain that 'Bernhard is green and John left the football'.
Chances are about even that 'Bernhard is green and John left the football'.
It is almost certain that 'Bernhard is green and John left the football'.

  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
  0.8::factA.
  0.0::factB.
  0.7::factC.
  %hop1
  0.8::factX:-or(factA,factB).
  0.2::factY:-or(factA,factB).
  0.0::factZ:-and(factA,factC).

  %hop2
  conclusion:-and(factX,factC).

  query(conclusion).
  
'Bernhard is green and John left the football'.