We believe that John went to the garden. It is probably the case that Sandra left the football. It is highly likely that Julius is a frog. It is highly unlikely that if either 'Sandra left the football' or 'Julius is a frog' but not both then Gertrude is a sheep. It is almost certain that if 'Sandra left the football' or 'John went to the garden' or both then Greg is a rhino. It is almost certain that if either 'John went to the garden' or 'Julius is a frog' but not both then Daniel took the milk.
There is a very good chance that 'Julius is a frog and Gertrude is a sheep'.
There is almost no chance that 'Julius is a frog and Gertrude is a sheep'.
There is a very good chance that 'Julius is a frog and Gertrude is a sheep'.

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

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

  query(conclusion).
  
'Julius is a frog and Gertrude is a sheep'.