
There are five levels of tracing available in Algernon:

   default-trace (dt)	   --	The current default trace in Algernon is the 'dot-trace'.
				The dot-trace prints out a single character for each significant
				event.  The characters can then be expanded by executing the
				command "view-dot-trace" (vdt) (this command is not supported
				on all machines).  The currently used characters are the following:

				p ---	The beginning of a new predicate (in the current path).
				! ---	A top level assertion.
				? ---	A top level query.

				n --- 	(Any number) The assertions and queries for interation n.
				. ---	The application of a rule.
				, ---	The reapplication of a rule (when a relevant new fact has been learned).
				+ ---	The creation of a new frame.
				> ---	The completion of an if-added rule.
				
				
				[ ---	The beginning of a partion update.
				] ---	The new facts added by the partition update.

				a ---	The addition of an assumption.
				d ---	The dropping of an assumption.
				->c<- --- A contradiction.
					c  represents the predicate.
					-> represents the assumptions under which c is believed.
					<- represents the assumptions under which c is disbelieved.

   trace-all (ta)          -- 	Trace everything.
				In any but the smallest examples produces a great deal
				of output.

   trace-logic (tl)        -- 	Trace queries, assertions, and rule applications.
				This level of tracing is useful for observing the action
				of rules, but on most examples still produces lots
				of output.

   trace-interest (ti)     -- 	Trace just "interesting" events.
				Interesting events are primarily the addition of new facts
				to the knowledge-base and the detection of contradictions.
				The application of individual rules is not shown, but
				the query list and assertion list are shown on every interation
				as the rules are applied.

   trace-off (to)          --   No tracing.
