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Removing a Relation

You use a conclude action with the word not to remove a relation instance between two relation items or classes:

conclude that item is not relation-name    item

For a description the arguments, see Creating a Relation.

For example, this button breaks a relation between computer-1 and computer-2, which are instances of the COMPUTER class. In the relation definition, First-class and Second-class both specify the COMPUTER class.

Similarly, you can break relations between more than one instance of a class by using a class expression. For example, this statement breaks all relations between every instance of the COMPUTER class.

conclude that every computer
	is not in-communication-with
	every computer

Removing Relations by Deleting Items

If you delete an item that participates in a relation, G2 removes the relation.

Deleting a relation in this manner does not cause forward chaining in rules. For more information, see Invoking Rules when a Relation is Deleted.

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