There is a very good chance that Brian is a swan. It is highly likely that Sumit is tired. There is a very good chance that Bernhard is a rhino. It is likely that if either 'Brian is a swan' or 'Sumit is tired' but not both then Emily is a sheep. There is a very good chance that if either 'Bernhard is a rhino' or 'Sumit is tired' but not both then Lily is green. It is highly unlikely that if 'Sumit is tired' or 'Brian is a swan' or both then John went to the hallway.
It is certain that 'John went to the hallway and Bernhard is a rhino'.
It is highly unlikely that 'John went to the hallway and Bernhard is a rhino'.
It is certain that 'John went to the hallway and Bernhard is a rhino'.

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

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

  query(conclusion).
  
'John went to the hallway and Bernhard is a rhino'.