It is highly unlikely that Emily is a wolf. There is a very good chance that Sandra dropped the milk. We believe that Winona is a cat. It is highly unlikely that if 'Sandra dropped the milk' or 'Emily is a wolf' or both then Jeff went to the hallway. We believe that if 'Sandra dropped the milk' or 'Emily is a wolf' or both then Greg is a rhino. It is probably the case that if 'Winona is a cat and Emily is a wolf' then Bernhard is a frog.
There is almost no chance that 'Greg is a rhino and Bernhard is a frog'.
There is almost no chance that 'Greg is a rhino and Bernhard is a frog'.
It is probably the case that 'Greg is a rhino and Bernhard is a frog'.

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

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

  query(conclusion).
  
'Greg is a rhino and Bernhard is a frog'.