Using eXpertise2Go: Determining why a question was asked
  To find a value for the recommended action, a value for the result of trying the starter is needed to try this rule:

If the result of switching on the headlights is nothing happens
or the result of trying the starter is nothing happens

Then the recommended action is recharge or replace the battery
The expert system's inference engine uses rules in its knowledge base to produce new facts based on values you input. The explanation shows which facts are sought and the if/then rule the inference mechanism is currently evaluating.
 
A value for the result of switching on the headlights has already been determined

A value for the result of trying the starter has not yet been determined
Each of the parameters in the if part of the rule is listed, along with the current state of knowledge of a value for that parameter.
 

WebESIE v1.0 Copyright © 2001 by eXpertise2Go.com. All rights reserved.
Auto diagnosis knowledge base Copyright © 2001 by eXpertise2Go.com. All rights reserved.
After examining this information, you may return to the question to select and input your response. If the knowledge base incorporates a rule forum, a button providing forum access is shown.
You may select the name of any of the currently known facts from the drop-down select list, then click Explain to see how its value(s) was obtained. Or, you may click the Save all button to store all of the values you have input so far in a "cookie." After either of these actions, you will return to this screen.
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