From Charles Hockett (1966), "The Problem of Universals in Language"

The Search for Universals Through Comparison with Animal Systems

"The design-features listed below are found in every language on which we have reliable information, and each seems to be lacking in at least one known animal communicative system. They are not all logically independent, and do not necessarily all belong to our defining list for language--a point to be taken up separately..."

1. Mode of communication-vocal-auditory, tacticle-visual, or chemical-olfactory

2. Rapid Fading: Message does not linger in time or space after production.

3. Interchangeability: individuals who use a language can both send and receive any permissible message within that communication system.

4. Feedback: users of a language can perceive what they are transmitting and can make corrections if they make errors.

5. Specialization: the direct-energetic consequences of linguistic signals are usually biologically trivial; only the triggering effects are important.

6. Semanticity: there are associative ties between signal elements and features in the world; in short, some linguistic forms have denotations.

7. Arbitrariness: there is no logical connection between the form of the signal and its meaning.

8. Discreteness: messages in the system are made up of smaller, repeatable parts; the sounds of language (or cheremes of a sign) are perceived categorically, not continuously.

9. Displacement: linguistic messages may refer to things remote in time and space, or both, from the site of the communication.

10. Productivity: users can create and understand completely novel messages.

10.1. In a language, new messages are freely coined by blending, analogizing from, or transforming old ones. This says that every language has grammatical patterning.

10.2. In a language, either new or old elements are freely assigned new semantic loads by circumstances and context. This says that in every language new idioms constantly come into existence.

11. Cultural transmission: the conventions of a language are learned by interacting with more experienced users.

12. Duality (of Patterning): a large number of meaningful elements are made up of a conveniently small number of meaningless but message-differentiating elements.

13. Prevarication: linguistic messages can be false, deceptive, or meaningless.

14. Reflexiveness: In a language, one can communicate about communication.

15. Learnability: A speaker of a language can learn another language.

"There is...a sense in which [productivity], displacement, and duality...can be regarded as the crucial, or nuclear, or central properties of human language."