Communication inputs and outputs are in an I-O language whose sentences are meaningful speech acts approximately in the sense of philosophers and linguists. These include questions, answers, offers, acceptances, declinations, requests, permissions and promises.

Entities in the same semantic neighborhood but without a typed relation to this one — candidates for new edges or unrecognized duplicates.

• Elephant programs that interact non-trivially with the outside world can have both input-output specifications, relating the programs inputs and outputs, and accomplishment specifications concerning what the program accomplishes in the world. These concepts are respectively generalizations of the philosophers' illocutionary and perlocutionary speech acts.claim0.799
  Fifth abstract claim.
• Speech acts are necessary in common sense informatic situations where agents with different goals and knowledge interact.claim0.771
  McCarthy's fundamental position: most important features of speech acts are independent of whether agents are human or machine.
• Many kinds of human speech act are relative to social institutions that change, and the exchange of speech acts among computer programs will often involve the design of new institutions prescribing the effects of speech acts.claim0.771
  Claim about designing institutions for program speech acts.
• A form language able to produce life must be a system of transformations which allows living centers to be created, one by one.claim0.764
  Defines the requirement for an effective form language.
• I-O languageconcept0.760
  The language of inputs and outputs in Elephant, composed of meaningful speech act sentences.
• Abstract performatives include purely internal actions such as commitments not necessarily expressed in output, but on whose fulfillment the correctness of the program depends.quote0.759
  Definition of abstract performative, a core invention of the paper.
• Perhaps we will need three levels of specification, internal, input-output and accomplishment.hypothesis0.759
  Speculation about specification hierarchy.
• Input-Output Specificationconcept0.756
  Specification relating a program's inputs and outputs, analogous to illocutionary correctness.