Chances are slight that John discarded the milk. It is certain that Julius is a frog. There is a very good chance that Brian is green. It is probably not the case that if 'John discarded the milk' or 'Julius is a frog' or both then Sandra left the football. It is probable that if 'Brian is green and Julius is a frog' then Lily is a rhino. We doubt that if 'Julius is a frog and Brian is green' then Daniel dropped the apple.
There is a very good chance that 'John discarded the milk and Brian is green'.
Chances are slight that 'John discarded the milk and Brian is green'.
There is a very good chance that 'John discarded the milk and Brian is green'.

  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.
  1.0::factB.
  0.8::factC.
  %hop1
  0.25::factX:-or(factA,factB).
  0.7::factY:-and(factC,factB).
  0.2::factZ:-and(factB,factC).

  %hop2
  conclusion:-and(factA,factC).

  query(conclusion).
  
'John discarded the milk and Brian is green'.