The predicate named shibboleth.Conditions.FALSE always returns false, regardless of input. 

The predicate named shibboleth.Conditions.TRUE always returns true, regardless of input. 

They require no parameterization and hence can be used by name.

Example

<resolver:AttributeDefinition xsi:type="Simple" xmlns="urn:mace:shibboleth:2.0:resolver:ad" id="never resolved"
        activationConditionRef="shibboleth.Conditions.FALSE"/>

<resolver:AttributeDefinition xsi:type="Simple" xmlns="urn:mace:shibboleth:2.0:resolver:ad" id="always resolved"
        activationConditionRef="shibboleth.Conditions.TRUE"/>