I need to create a simple expert system (Knowkedge based). Following are the requirement need to be fullfill. 1.the inference engine should be able to do backward and forward chaining. 2.Define a predicate alltrue(L)thats check all facts true or not. 3.Define Predicate addfact that can add fact to the knowledge base. I need an urgent help, if any one can help me to create this assignment or atleast provide me some tutorial for doing this. Thanks in Advance. Junaid Khan 0736835366

There exist some open source implementations on expert systems if you want to see some code. Also knowing RETE algorithms is of tremendous help.

[EDIT]And really creating more than a very basic system is not an easy feat and does take time and skill.[/EDIT]

I did all of that back "in the days", but it was in Scheme (lisp). This is fairly straigthforward to implement in a functional language, only the unification is a bit more tricky.