13. An electronic device, comprising: one or more processors; memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for: registering, by a processor, a service for use in conjunction with an active ontology by specifying at least one of: one or more active processing elements that the service can accept; and one or more active processing elements that the service cannot accept; filtering, by the active ontology, at least one request for services to the service in accordance with the one or more active processing elements specified by the service; wherein: the active ontology is configured to perform natural language processing on user input, the natural language processing performed in response to input facts relating to events collected from a user's environment, and the active ontology comprises a plurality of active processing elements configured to match specific types of facts.
13. An electronic device, comprising: one or more processors; memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for: registering, by a processor, a service for use in conjunction with an active ontology by specifying at least one of: one or more active processing elements that the service can accept; and one or more active processing elements that the service cannot accept; filtering, by the active ontology, at least one request for services to the service in accordance with the one or more active processing elements specified by the service; wherein: the active ontology is configured to perform natural language processing on user input, the natural language processing performed in response to input facts relating to events collected from a user's environment, and the active ontology comprises a plurality of active processing elements configured to match specific types of facts. 23. The electronic device of claim 13 , wherein at least one of the plurality of active processing elements is configured to send at least one fact to at least one other active processing element.