 |
|
|
|
|
|
|
|
|
|
|
|
| n |
Define:
KB ├i α = sentence α can be derived from KB by
|
|
|
|
|
procedure i
|
|
|
| n |
Soundness: i is sound if whenever KB ├i α, it is
also true
|
|
|
|
|
that KB╞
α
|
|
|
| n |
Completeness: i
is complete if whenever KB╞ α, it is also
|
|
|
true that KB ├i α
|
|
| n |
Preview:
we will define a logic (first-order logic) which is
|
|
|
expressive
enough to say almost anything of interest, and
|
|
for
which there exists a sound and complete inference
|
|
|
procedure.
|
|
|
| n |
That
is, the procedure will answer any question whose
|
|
|
answer
follows from what is known by the KB.
|
|
