It is impossible that Winona is a sheep. There is little chance that Emily is a wolf. We doubt that Brian is a lion. It is highly likely that if 'Brian is a lion and Winona is a sheep' then Bernhard is white. We believe that if 'Winona is a sheep' or 'Brian is a lion' or both then Fred discarded the apple. It is likely that if 'Brian is a lion and Winona is a sheep' then John left the football.
It is unlikely that 'John left the football' or 'Brian is a lion' or both.
It is unlikely that 'John left the football' or 'Brian is a lion' or both.
We believe that 'John left the football' or 'Brian 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
  0.0::factA.
  0.1::factB.
  0.2::factC.
  %hop1
  0.9::factX:-and(factC,factA).
  0.75::factY:-or(factA,factC).
  0.7::factZ:-and(factC,factA).

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

  query(conclusion).
  
'John left the football' or 'Brian is a lion' or both.