Chances are slight that Mary went to the garden. It is likely that Gertrude is a cat. It is almost certain that Lily is a swan. There is little chance that if either 'Mary went to the garden' or 'Lily is a swan' but not both then Brian is green. It is highly unlikely that if 'Lily is a swan and Gertrude is a cat' then Julius is a lion. There is almost no chance that if either 'Gertrude is a cat' or 'Mary went to the garden' but not both then John took the football.
Chances are slight that 'Mary went to the garden' or 'Julius is a lion' or both.
Chances are slight that 'Mary went to the garden' or 'Julius is a lion' or both.
It is probably the case that 'Mary went to the garden' or 'Julius is a lion' 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.
  0.7::factB.
  0.95::factC.
  %hop1
  0.1::factX:-xor(factA,factC).
  0.05::factY:-and(factC,factB).
  0.02::factZ:-xor(factB,factA).

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

  query(conclusion).
  
'Mary went to the garden' or 'Julius is a lion' or both.