It is highly likely that Winona is a wolf. It is probably the case that Gertrude is a cat. It is certain that Mary went to the garden. It is highly likely that if 'Winona is a wolf' or 'Mary went to the garden' or both then Brian is green. Chances are slight that if 'Gertrude is a cat' or 'Winona is a wolf' or both then John got the apple. It is impossible that if either 'Winona is a wolf' or 'Gertrude is a cat' but not both then Greg is gray.
There is almost no chance that 'Gertrude is a cat' or 'Brian is green' or both.
It is almost certain that 'Gertrude is a cat' or 'Brian is green' or both.
There is almost no chance that 'Gertrude is a cat' or 'Brian is green' 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
  0.9::factA.
  0.7::factB.
  1.0::factC.
  %hop1
  0.9::factX:-or(factA,factC).
  0.1::factY:-or(factB,factA).
  0.0::factZ:-xor(factA,factB).

  %hop2
  conclusion:-or(factB,factX).

  query(conclusion).
  
'Gertrude is a cat' or 'Brian is green' or both.