ne to mechanisms (where known) for adjusting
    our symbols?  Let me provide an example of this.  Suppose that we have some graph that models
    some aspect of NL dialogue.  Let's say it performs well within its limited domain and within
    that domain uses binary logic -- but what happens when a trusted assertion is introduced
    that contradicts the structure?  Classical logic in this case can do no more than report
    the contradiction.

SR: But perhaps there is a logic that could do more.  Suppose 