It is probably not the case that Mary took the football. There is a very good chance that Julius is a swan. There is a very good chance that John put down the apple. There is a better than even chance that if either 'Mary took the football' or 'John put down the apple' but not both then Greg is a rhino. There is a better than even chance that if 'John put down the apple and Julius is a swan' then Brian is a frog. It is improbable that if 'Mary took the football' or 'Julius is a swan' or both then Emily is a wolf.
It is unlikely that 'Greg is a rhino and Brian is a frog'.
It is unlikely that 'Greg is a rhino and Brian is a frog'.
It is certain that 'Greg is a rhino and Brian 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
  0.25::factA.
  0.8::factB.
  0.8::factC.
  %hop1
  0.6::factX:-xor(factA,factC).
  0.6::factY:-and(factC,factB).
  0.1::factZ:-or(factA,factB).

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

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