There is a better than even chance that Mary took the football. It is certain that Brian is white. It is highly likely that Emily is a wolf. It is probable that if 'Brian is white and Emily is a wolf' then Daniel put down the milk. It is certain that if 'Brian is white and Emily is a wolf' then John went to the garden. It is improbable that if 'Mary took the football and Emily is a wolf' then Julius is a rhino.
There is a better than even chance that 'Mary took the football' or 'Julius is a rhino' or both.
There is a better than even chance that 'Mary took the football' or 'Julius is a rhino' or both.
Chances are slight that 'Mary took the football' or 'Julius is a rhino' or both.

  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
  0.6::factA.
  1.0::factB.
  0.9::factC.
  %hop1
  0.7::factX:-and(factB,factC).
  1.0::factY:-and(factB,factC).
  0.1::factZ:-and(factA,factC).

  %hop2
  conclusion:-or(factA,factZ).

  query(conclusion).
  
'Mary took the football' or 'Julius is a rhino' or both.