It is improbable that Gertrude is a wolf. There is almost no chance that Mary went to the garden. It is probably not the case that Brian is green. It is highly unlikely that if 'Mary went to the garden and Gertrude is a wolf' then Winona is a cat. It is probably the case that if 'Gertrude is a wolf' or 'Mary went to the garden' or both then Julius is a swan. There is a better than even chance that if 'Mary went to the garden' or 'Gertrude is a wolf' or both then Jeff dropped the apple.
It is certain that 'Mary went to the garden' or 'Gertrude is a wolf' or both.
There is little chance that 'Mary went to the garden' or 'Gertrude is a wolf' or both.
It is certain that 'Mary went to the garden' or 'Gertrude is a wolf' 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
  0.1::factA.
  0.02::factB.
  0.25::factC.
  %hop1
  0.05::factX:-and(factB,factA).
  0.7::factY:-or(factA,factB).
  0.6::factZ:-or(factB,factA).

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

  query(conclusion).
  
'Mary went to the garden' or 'Gertrude is a wolf' or both.