next up previous
Next: The proposal of Up: The problem statement Previous: Language

Knowledge retrieval

Current indexing and keyword search techniques provide only a limited performance in accessing heterogeneous knowledge sources. A more advanced approach is to annotate the opaque information by simple sentences and fetch the piece of data whose annotation matches a query. This is still fairly limited in the following sense: Consider a picture in a library of news photographs, annotated ``A soldier holding a gun to a woman's head.'' It is conceivable to retrieve this photograph by a query such as: ``Show me the picture of someone holding a gun.'' But to fetch the same picture based on queries like: ``Show me a picture of a frightened person'', or ``a man threatening a woman,'' requires knowing about the meaning of the symbols.

What do the symbols of our current programs mean? Think about the link between the symbol ``fly'' and the action of flying in the real world. The only connection seems to be the human who is using or writing the program. He is responsible from coming up with this concept in the first place, and then learning the assignment of this particular sign to it. In other words, the symbols in systems such as ZOOKEEPER take their meanings in the eye of the observer.

Cyc's goal is to provide a solution to exactly this problem. It is assumed that if enough background knowledge is explicitly collected, programs can use this source to answer trivial questions and make obvious inferences about their own symbols.



Deniz Yuret
Tue Apr 1 21:26:01 EST 1997