It is almost certain that Greg is green. We believe that Mary went to the kitchen. It is probably the case that Brian is a lion. It is certain that if 'Greg is green and Mary went to the kitchen' then Winona is a sheep. It is unlikely that if either 'Greg is green' or 'Brian is a lion' but not both then John put down the apple. It is unlikely that if 'Greg is green and Brian is a lion' then Bernhard is a frog.
It is impossible that 'Brian is a lion' or 'Mary went to the kitchen' or both.
It is almost certain that 'Brian is a lion' or 'Mary went to the kitchen' or both.
It is impossible that 'Brian is a lion' or 'Mary went to the kitchen' 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
  0.95::factA.
  0.75::factB.
  0.7::factC.
  %hop1
  1.0::factX:-and(factA,factB).
  0.2::factY:-xor(factA,factC).
  0.2::factZ:-and(factA,factC).

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

  query(conclusion).
  
'Brian is a lion' or 'Mary went to the kitchen' or both.