The Shifting Terminological Space: An Impediment to Evolvability

In an expert system, rules or methods interact by creating situations to which other rules or methods respond. We call the language in which these situations are represented the terminological space. In most expert systems, terms in this language often lack an independent definition, in which case they are implicitly defined by the way the rules or methods react to them. We argue that this hampers evolution, and argue for a separate, independently defined terminological space that is automatically maintained.