Chances are about even that Winona is a sheep. There is almost no chance that Julius is a rhino. There is a very good chance that Mary took the football. There is a very good chance that if 'Julius is a rhino' or 'Mary took the football' or both then Greg is green. It is almost certain that if 'Mary took the football' or 'Julius is a rhino' or both then Brian is a frog. It is highly likely that if either 'Mary took the football' or 'Winona is a sheep' but not both then Bernhard is a swan.
There is a better than even chance that 'Mary took the football and Greg is green'.
There is a better than even chance that 'Mary took the football and Greg is green'.
There is little chance that 'Mary took the football and Greg 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
  0.5::factA.
  0.02::factB.
  0.8::factC.
  %hop1
  0.8::factX:-or(factB,factC).
  0.95::factY:-or(factC,factB).
  0.9::factZ:-xor(factC,factA).

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

  query(conclusion).
  
'Mary took the football and Greg is green'.