Language

Type of psychology: Cognition; language
Fields of study: Cognitive processes; thought
Language is a system of arbitrary symbols that can be combined in conventionalized
ways to express ideas, thoughts, and feelings. Various theories and models have been
constructed to study, describe, and explain language acquisition, language processing,
and its relation to thought and cognition.

Key concepts
• displacement
• grammar
• language faculty
• linguistic relativity
• morphology
• phonology
• pragmatics
• semantics
• syntax
• universal grammar

Language is a system of arbitrary symbols that can be combined in conventionalized
ways to express ideas, thoughts, and feelings. Language has been
typically seen as uniquely human, separating the human species from other
animals. Language enables people of all cultures to survive as a group and
preserve their culture. The fundamental features of human language make
it extremely effective and very economical. Language uses its arbitrary symbols
to refer to physical things or nonphysical ideas; to a single item or a
whole category; to a fixed state or to a changing process; to existent reality
or to nonexistent fiction; to truths or to lies.

Language is systematic and rule-governed. Its four component subsystems
are phonology, semantics, grammar, and pragmatics. The phonological
system uses phonemes (the smallest speech sound units capable of differentiating
meanings) as its building blocks to form syllables and words
through phonemic rules. For example, /m/ and /n/ are two different phonemes
because they differentiate meaning as in /mTt/ (meat) versus /nTt/
(neat), and “meat” has three phonemes of /m/, /T/, and /t/ placed in a
“lawful” order in English to form one syllable. The semantic system makes
language meaningful. It has two levels: Lexical semantics refers to the word
meaning, and grammatical semantics to the meaning derived from the combinations
of morphemes (the smallest meaning units) into words and sentences.
“Beds,” for example, has two morphemes, “bed” as a free morpheme
means “a piece of furniture for reclining or sleeping,” and “s” as a bound
morpheme means “more than one.”
The grammatical system includes morphology and syntax. Morphology specifies rules to form words (for example, prefixes, suffixes, grammatical
morphemes such as “-ed,” and rules to form compound words such as
“blackboard”). Syntax deals with rules for word order in sentences (such as,
“I speak English,” but not “I English speak”). Furthermore, the syntax of
human language has four core elements, summarized in 1999 by Edward
Kako as discrete combinatorics (each word retains its general meaning even
when combined with other words), category-based rules (phrases are built
around word categories), argument structure (the arguments or the participants
involved in an event, labeled by verbs, are assigned to syntactic positions
in a sentence), and closed-class vocabulary (the grammatical functional
words, such as “the,” “on,” or “and,” are usually not open to addition
of new words).

The fourth subsystem in human language is the pragmatic system. It involves
rules to guide culture-based, appropriate use of language in communication.
For example, people choose different styles (speech registers) that
they deem appropriate when they talk to their spouses versus their children.
Other examples include the use of contextual information, inferring the
speaker’s illocutionary intent (intended meaning), polite expressions, conversational
rules, and referential communication skills (to speak clearly and
to ask clarification questions if the message is not clear).
Language is creative, generative, and productive. With a limited number
of symbols and rules, any language user is able to produce and understand
an unlimited number of novel utterances. Language has the characteristic
of displacement; that is, it is able to refer to or describe not only items and
events here and now but also items and events in other times and places.