A Role is the only concept in Perspectives that has Properties. Roles are the Entities of Perspectives but there is a difference that is essential to the philosophy of Perspectives. An Entity is and absolute collection of Properties, independent of the context in which it is relevant. In contrast, a Role has Properties dependent on the Context in which it is relevant.
Perspectives defines three different types of Roles: Role, User and Bot. Users and Bots are called Actors and can be the subject of Actions. Roles can only be the object of Actions. Of course, actors can also be the objects of Actions because others can do things with the Objects of Actions.
Roles are filled with other Roles. This is modelled by the "in" connector, the only connector, in the diagramming language. When a Role is filled by another Role the Properties of the first become available in de second. This implements the notion of inheritance in Perspectives. When an Actor is filled by another Actor, not only the Properties of the first become available in the second, more importantly the Actions of the first become available in the second.