A State is a Class_of_physical_individual that indicates the nature of an individual product at an instant.
A State can be a specification for the condition of an individual product at an instant.
EXAMPLE - 'Part type XYZ_123 at maximum power' is a State. Many instants in the life of an individual part of type XYZ_123 can be members of this State.
EXAMPLE - 'Part type XYZ_123 after 100000 hours' is a State. No more than one instant in the life of an individual part of type XYZ_123 can be a member of this State.
EXPRESS specification:
*) ENTITY State SUBTYPE OF (Class_of_physical_individual); END_ENTITY; (*