Language Acquisition and Learning: Krashen, Chomsky, Skinner, Vygotsky and Piaget

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Acquisition versus learning

Stephen Krashen separated two ways of developing a language. Acquisition is subconscious: the child picks up the language while using it for real purposes, as every child picks up the home language without lessons. Learning is conscious: knowing the rules and being able to state them, the way students study grammar for an examination. Krashen held that only acquired knowledge drives fluent speech and that learning does not turn into acquisition. A teacher who only explains rules produces children who can define a noun but cannot speak, while a classroom rich in stories, talk and meaningful reading lets the language be acquired.

The monitor, input and affective filter

In the monitor hypothesis, learned rules act only as an editor that checks output, and the monitor works only when the speaker has time, is focused on correctness and knows the rule; that is why a child may get a written grammar exercise right yet make the same error in free speech. Krashen called learners who check everything over-users, those who rely only on feel under-users, and those who balance the two optimal users. The input hypothesis says we acquire by understanding messages slightly beyond our current level, i+1, with the help of context, pictures and gestures; speaking emerges on its own once enough comprehensible input has built up, so a silent period in a new learner is normal. The affective filter hypothesis says anxiety, low motivation and low self-confidence raise a mental block that stops input from being acquired, so a child who is laughed at for a wrong word learns less even from good input. The natural order hypothesis adds that structures are acquired in a predictable order that teaching cannot rearrange.

Behaviourist and nativist views

B.F. Skinner, in Verbal Behavior (1957), treated language as behaviour shaped by operant conditioning: the child imitates, adults reinforce correct forms, and repeated responses become habits. This explains why children pick up the words and accent of their surroundings, and it lies behind drill methods. Noam Chomsky's review of the book in 1959 argued that it cannot explain why children produce sentences they have never heard, make errors such as goed and mouses that no adult models, and master a complex grammar from limited and imperfect speech, the poverty of the stimulus argument. Chomsky proposed an innate Language Acquisition Device (LAD) and a universal grammar, principles common to all human languages, so that exposure only sets the details of a particular language. He also separated competence, the speaker's internal knowledge of the language, from performance, its actual use.

Vygotsky and Piaget on language and thought

For Lev Vygotsky language is social in origin and the most important cultural tool for thinking. In Thought and Language (Russian original 1934), thought and speech grow from separate roots and meet at about the age of 2; speech then moves from social speech, used to communicate, to private speech, the audible self-talk with which children of about 3 to 7 years guide themselves through a task, and finally to silent inner speech that directs thinking. Jean Piaget, in The Language and Thought of the Child (1923), called the same self-talk egocentric speech, a sign that the young child cannot yet take another person's point of view, which fades as the child becomes social; he also described the collective monologue, in which children in a group each talk aloud without really responding to one another. For Piaget language reflects thought, so concepts must develop before words for them become meaningful. Vygotsky's view supports talk, group work and scaffolding; Piaget's supports concrete experience before vocabulary.

Interaction and the critical period

Interactionists combine the two sides. Jerome Bruner accepted an inborn readiness but argued that adults provide a Language Acquisition Support System (LASS): routines like naming pictures in a book, in which the adult does most of the work at first and hands over more as the child grows. The critical period hypothesis, put forward by Eric Lenneberg in 1967, holds that language is acquired most easily from early childhood until about puberty, as the brain matures. The case of Genie, found in 1970 at the age of 13 after years of isolation, who learnt many words but never mastered grammar, is often cited. Many researchers now prefer the term sensitive period: older learners can learn languages well, but a native-like accent is far more likely when exposure begins early. NEP 2020 notes that children learn languages most quickly between 2 and 8 years of age.

What CTET asks

Acquisition is helped by exposure to meaningful language, a fear-free atmosphere and chances to use language, not by memorising rules. A child who says I goed home has worked out a rule for herself, which supports the nativist and cognitive views, and the teacher should model the correct form rather than punish. Know the pairs: LAD and universal grammar with Chomsky, operant conditioning with Skinner, private speech with Vygotsky, egocentric speech with Piaget, LASS with Bruner, i+1 and the affective filter with Krashen, and the critical period with Lenneberg.

Key facts

Krashen: acquisition is subconscious (how every child picks up the home language); learning is conscious knowledge of rules; learned rules only act as a monitor that edits output.
Input hypothesis: comprehensible input at i+1, one step above the learner's level; speaking emerges after enough input, so a silent period in a new learner is normal.
Affective filter: anxiety, low motivation and low self-confidence block input; a teacher lowers it with a fear-free class, praise for attempts and no ridicule of errors.
Skinner, Verbal Behavior (1957): language is verbal behaviour learnt through imitation, reinforcement and habit formation; the basis of drill methods.
Chomsky (review of Skinner, 1959): innate LAD, universal grammar, poverty of the stimulus; competence (knowledge of language) vs performance (actual use).
Vygotsky: social speech, then private speech (about 3 to 7 years), then inner speech; language is a cultural tool of thought. Piaget: egocentric speech and collective monologue; thought comes before language.
Bruner: LASS (Language Acquisition Support System), the adult routines that support the child's inborn readiness for language.
Critical period: Eric Lenneberg (1967), from early childhood to puberty; Genie (found 1970, aged 13) is the classic case; NEP 2020: children learn languages fastest between 2 and 8.
A child who says goed or foots is over-generalising a rule she worked out herself, evidence that language is not learnt by imitation alone.

Quick revision

Krashen: acquisition (subconscious) vs learning (conscious); monitor edits output; over-, under- and optimal users; input i+1; silent period; affective filter; Skinner, Verbal Behavior 1957: imitation, reinforcement; Chomsky 1959 review: LAD, universal grammar, poverty of stimulus, competence vs performance; Vygotsky: social, private (3-7), inner speech; Piaget: egocentric speech, collective monologue; Bruner: LASS; Lenneberg 1967: critical period; Genie.

Practise this topic

All 8 lessons on Language Pedagogy (Language I and Language II)