Inference

Inference: 

•KB ├i α = sentence α can be derived from KB by procedure i

•Soundness: i is sound if whenever KB ├i α, it is also true that KB╞ α

•Completeness: i is complete if whenever KB╞ α, it is also true.

 

•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.

•That is, the procedure will answer any question whose answer follows from what is known by the KB.