The term "a priori" is used to clarify when such arcs will be
declared. The term "built-in" does not limit its presence to a TM
Application. The usage here accords with that reported in *Dictionary of
Philosophy* by Dagobert Runes, 1983, page 31 "...In Kant's doctrine, all
the necessary conditions of experience (i.e., forms and categories) are
a priori. Whatever is a priori must possess universal and necessary
validity..." A priori arcs, nodes, assertions, are required to be
present in a TM Application as machinery that supports the arcs, nodes
and assertions found in topic maps.

Removed connectedness, a priori assertion and assertion are defined
elsewhere.