2.5 Stand-alone relations

While it is possible for concepts not to have any arcs attached to themselves, this is not possible for relations. A relation must have at least one arc that belongs to it.

For example, the following is not a well-formed conceptual graph:

   (On)
   Ill-formed conceptual graph

However, the following is a well-formed conceptual graph, since the relation (In) has at least one arc that belongs to it (in fact, it has two):

   [Bird]->(In)->[SycamoreTree]
   Well-formed conceptual graph

It means "There is a bird in a sycamore tree".


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