As we have defined it, the pattern matcher matches one input against one pattern. In el i za, we need to match each input against a number of patterns, and then return a result based on the rule that contains the first pattern that matches. To refresh your memory, here is the function use-el i za - rul es:

(defun use-eliza-rules (input)

"Find some rule with which to transform the input."

(some #'(lambda (rule)

( l e t ((result (pat-match (rule-pattern rule) input) 1)

( i f (not (eq result f a i l ) )

(sub1 is (switch-viewpoint result)

(random-el t (rul e-responses rul el 1) 1)

*eliza-rules*))