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    # KEHOME/knowledge/theory/KRdesign/knitchit.html
    # 1999/5/4
    # new syntax Sep/29/2002

    knowledge unit
    ==============
    A knowledge unit (knit) is a set of statements
    organized as an entity-relation concept-hierarchy
    and identified by a view name.

    	at view=tabula_rasa

    identifies a new knit, ready to be filled with specific
    knowledge.

    The top-level concepts of tabula_rasa include the
    axiomatic concepts (e.g., entity, relation, attribute, action,
    identify) which are used to specify all knowledge.

    The bottom-level concepts of any knit include the axiomatic
    percepts (integrated sense data) which are the internal
    measurement of external reality.

    The intermediate-level non-axiomatic concepts are chosen
    by each person, according to his/her purpose.
    The two fundamental purposes are unit-economy
    (minimize the size of the knowledge representation)
    and selective focus (on particular characteristics of entities).

    change unit
    ===========
    A change unit (chit) is a set of action/event statements
    identified by event names and the space-time at which they occur.
    These statements:

    	at space=s,time=t,view=v
    	entity do action=e od aobject done
    	e changes eobject \
    			from attribute=initial \
    			to   attribute=final

    identify a new chit with event e.
    s identifies where e occurs.
    t identifies when  e occurs.

General References