We believe that Brian is a frog. It is probably not the case that Emily is a mouse. It is almost certain that Sandra left the milk. There is a better than even chance that if 'Brian is a frog' or 'Sandra left the milk' or both then Jessica is a sheep. Chances are about even that if 'Brian is a frog and Sandra left the milk' then John moved to the garden. It is probable that if 'Sandra left the milk' or 'Brian is a frog' or both then Lily is a lion.
It is probably not the case that 'John moved to the garden' or 'Lily is a lion' or both.
There is a very good chance that 'John moved to the garden' or 'Lily is a lion' or both.
It is probably not the case that 'John moved to the garden' or 'Lily 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
  0.75::factA.
  0.25::factB.
  0.95::factC.
  %hop1
  0.6::factX:-or(factA,factC).
  0.5::factY:-and(factA,factC).
  0.7::factZ:-or(factC,factA).

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

  query(conclusion).
  
'John moved to the garden' or 'Lily is a lion' or both.