It is highly likely that Jeff left the football. It is highly unlikely that Antoine is bored. It is almost certain that Lily is a rhino. There is almost no chance that if 'Antoine is bored and Jeff left the football' then Bernhard is green. We believe that if either 'Lily is a rhino' or 'Jeff left the football' but not both then Fred is in the school. It is highly unlikely that if 'Antoine is bored' or 'Jeff left the football' or both then John went to the office.
It is impossible that 'Jeff left the football and Bernhard is green'.
It is impossible that 'Jeff left the football and Bernhard is green'.
It is almost certain that 'Jeff left the football and Bernhard is green'.

  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
  0.9::factA.
  0.05::factB.
  0.95::factC.
  %hop1
  0.02::factX:-and(factB,factA).
  0.75::factY:-xor(factC,factA).
  0.05::factZ:-or(factB,factA).

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

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