It is unlikely that Emily is a wolf. It is likely that Bernhard is green. Chances are about even that Julius is yellow. Chances are slight that if 'Bernhard is green and Julius is yellow' then Lily is a frog. We believe that if 'Emily is a wolf and Julius is yellow' then Gertrude is a sheep. It is highly likely that if 'Julius is yellow' or 'Bernhard is green' or both then John left the football.
It is unlikely that 'John left the football and Emily is a wolf'.
It is unlikely that 'John left the football and Emily is a wolf'.
It is highly likely that 'John left the football and Emily is a wolf'.

  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
  0.2::factA.
  0.7::factB.
  0.5::factC.
  %hop1
  0.1::factX:-and(factB,factC).
  0.75::factY:-and(factA,factC).
  0.9::factZ:-or(factC,factB).

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

  query(conclusion).
  
'John left the football and Emily is a wolf'.