Portrait of Charles F. Hockett. Cornell University.

In 1959, Charles F. Hockett, an American linguist, published “Animal ‘Languages’ and Human Language,” in which he articulates seven key properties of human language to determine how it functions and how it compares to other species’ languages. This is done partly in an effort to challenge the presumption that human language is somehow entirely unique to that of other species (such as bees, sticklebacks, waterfowl, and gibbons) — a tension point in the wake of Darwin’s “Origin of Species” published a century earlier.

The first of properties, Hockett calls the duality of patterning. Humans are able to communicate in language by rearranging small, differentiated units of meaning to make seemingly infinite assertions. In Hebrew, for example, the particular alphabet begins in the symbol ‘א’ and ending in the symbol ‘א’ .’ת’ assumes a meaning by virtue of appearing visually different than any other symbol in the alphabet. Furthermore, the sound associated is different between these two symbols. ‘א’ can be assembled beside any other letter in the Hebrew alphabet, in any quantity, to create meaning.

Second, Hockett describes the property of productivity. Productivity suggests that humans produce utterances based on previous utterances. Through this, humans build a series of utterances that have shared communal meanings within a specific culture. Hockett argues that this phenomenon is not unique to humans. Bees, for instance, are able to ‘dance’ in a way that each fellow bee subsequently understands; this act is productive in its shared communal meaning.

Third, Hockett notes the arbitrariness of human language. In English, the iconic representation of a word bears no similarity to that of the actual object it refers to. For example, the English word ‘computer’ does not resemble the likeness of a computer. The bee dance that Hockett brings up is not arbitrary. The actual manifestation of the bee dance is iconic, meaning that it actually embodies that which it is communicating: nectar nearby. Arbitrary language, too, is not unique to humans. Gibbons and various birds use arbitrary calls. In these cases, there is no correlation between the symbol and that which is references.

The fourth property is interchangeability. Because humans have assembled a shared series of utterances, we are able to assemble new utterances, and issue them novelly. Furthermore, when humans do create new sentences without having rehearsed them, we are still understood. The only bounds to which we are not able to theoretically say certain utterances are due to class, ritual, gender, and other social roles (in Judaism, for instance, it is not considered kosher to speak God’s true name aloud, though community members certainly could perform this in a physical sense).

The fifth property Hockett discusses is specialization, which can be further broken down into triggers and energy. When humans use language to prompt a question, it may trigger an energetic response, such as a reply, but the symbols themselves cannot cause the desired response to occur. Merely asking a question does nothing to affect the universe in itself, but because of its shared meaning, members of the language system are coaxed into an energetic response.

The sixth property is displacement. When humans speak of an object, that object may not exist in the present space and time but is rather indicated via a symbol (word) itself. For example, individuals are able to talk about a meal eaten last week or a relative that passed away years ago, even though neither of these objects are physically present any longer.

The final property Hockett discusses is cultural transmission. Due to a complex system of small units of meaning, repeated utterances, and the summed utility of all other properties discussed thereof, humans must teach and learn language in a somewhat formalized sense for it to continue in its present form. We cannot conceive of language innately — it is not coded by DNA — but rather must absorb such system from outsides sources within our culture (parents, formalized teachers, etc.).

Hockett suggests that human language ultimately began through productively repeated ‘blended’ utterances that developed an increased differentiation, and thus a larger selection of meaningful sounds. Productivity leads to arbitration and then had to be culturally transmitted to become embedded in the community. Man’s evolutionary ability to imitate well assisted immensely in this process. It is, however, the duality of patterning, that formalizes the understanding of human linguistics in an academic sense, and thus distinguishes humans from other life forms capable of communication. Human language is thus the product of a series of ‘lucky’ evolutionary advances that support an ability to build community meaning via symbols. Other species that can perfect imitation are in a better position to develop such complex communication systems evolutionarily. All in all, Hockett’s approach is very systematic.