Here''s an article on belief. I think situation calculus offers one of the more elegant methods of simulating belief and all of its complexities. I could go on more about it right now, but I am tired, and don''t have my explanatory powers regarding situation calculus fully tuned or refreshed. But I can say that if you aren''t familiar with it, your first exposure to it is likely to not nearly expose its capabilities and expressive power. It also is capable of planning. Its engine is nothing more than the unification process. It suffers from scaling, but there have been some successful optimization and compilation of its knowledge bases into partitioned graphs for efficient processing. Today I read an article (I don''t have the link handy) which discussed how to formalize it into an object oriented format using classes. (Not C++ classes, but a similar concept for organizing data). The article I read presented a framework which made the author better able to get a bird''s eye view of the knowledge, its structure and organization, and to build modules which seamlessly integrate into the existing knowledge base to enhance its power. ___________________________________

By the way, belief is an unbelievably thorny and complex theory which we use everyday without even really thinking about. Any system that provides an elegant solution to and gives one the full expressive power to model belief deserves attention.

Consider this:

John believes that Mary believes that within the Star Trek Universe, Captain Kirk believes that Dr. McCoy thinks Spock is too logical.

That is complex, but it is easy for us. Let me provide a real world example:

I believe that Wavinator believes that within the Star Trek Universe, Captain Kirk believes that Dr. McCoy beleives that that Spock is too logical.

Let''s say that in fact, Wavinator does NOT believe that within the Star Trek Universe, Captain Kirk beleives that Dr. McCoy believes that Spock is too logical.

I don''t believe the above statement, but it could be true, despite me not believing it.

We can make a great deal of assumptions from all of this, nonetheless. The Star Trek Universe is a hypothetical world within our world. Therefore, it is unreasonable that any agents in the Star Trek Universe would have beliefs about our world.

For example:

I believe that within the Star Trek Universe, Captain Kirk has no knowledge of Wavinator.

However, it is reasonable for me to adopt a beleif like this:

I believe that within the Star Trek Universe, Captain Kirk believes that Dr. McCoy believes that in the Moby Dick World, Ahab was a little too zealous in his pursuit of the giant whale.

In other words, I reasonably assume that the Star Trek Universe contains a history that is also ours, and that certain classical literature might be known to the agents in the Star Trek Universe.

However, I also believe that Ahab has no beleifs or knowledge of any agent in the Star Trek Universe. I also believe that all of the agents in the Start Universe do not believe that Ahab has any beliefs about anyone within the Star Trek Universe.

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