Krashen’s Hypotheses on Second Language Acquisition
Krashen’s Hypotheses on Second Language Acquisition
The Acquisition-Learning Hypothesis
The Acquisition-Learning Hypothesis is the most fundamental of all the hypotheses in Krashen’s theory and the most widely known among linguists and language practitioners. According to Krashen, there are two independent systems of second language performance: the acquired system and the learned system.
- The acquired system, or acquisition, is the product of a subconscious process very similar to the process children undergo when they acquire their first language. It requires meaningful interaction in the target language – natural communication – in which speakers are concentrated not in the form of their utterances, but in the communicative act.
- The learned system, or learning, is the product of formal instruction, and it comprises a conscious process which results in conscious knowledge about the language, for example, knowledge of grammar rules. According to Krashen, learning is less important than acquisition.
The Monitor Hypothesis
The Monitor Hypothesis explains the relationship between acquisition and learning and defines the influence of the latter on the former. The monitoring function is the practical result of the learned grammar. According to Krashen, the acquisition system is the utterance initiator, while the learning system performs the role of the monitor. The monitor acts in a planning, editing, and correcting function when three specific conditions are met:
- The second language learner has sufficient time at their disposal.
- They focus on form or think about correctness.
- They know the rule.
The role of the monitor is – or should be – minor, being used only to correct deviations from normal speech and to give speech a more polished appearance.
The Natural Order Hypothesis
The Natural Order Hypothesis suggests that the acquisition of grammatical structures follows a natural order which is predictable. For a given language, some grammatical structures tend to be acquired early while others late. This order seems to be independent of the learners’ age, first language background, and conditions of exposure. Although the agreement between individual acquirers was not always 100% in the studies, there were statistically significant similarities that reinforced the existence of a natural order of language acquisition. Krashen, however, points out that the implication of the natural order hypothesis is not that a language program syllabus should be based on the order found in the studies. In fact, he rejects grammatical sequencing when the goal is language acquisition.
The Input Hypothesis
The Input Hypothesis is Krashen’s attempt to explain how the learner acquires a second language. In other words, this hypothesis is Krashen’s explanation of how second language acquisition takes place. The Input Hypothesis is only concerned with acquisition, not learning. According to this hypothesis, the learner improves and progresses along the natural order when they receive second language input that is one step beyond their current stage of linguistic competence.
The Affective Filter Hypothesis
The Affective Filter Hypothesis states that a number of affective variables play a facilitative, but non-causal, role in second language acquisition. These variables include motivation, self-confidence, and anxiety. Krashen claims that learners with high motivation, self-confidence, a good self-image, and a low level of anxiety are better equipped for success in second language acquisition. Low motivation, low self-esteem, and debilitating anxiety can combine to raise the affective filter and form a mental block that prevents comprehensible input from being used for acquisition. In other words, when the filter is up, it impedes language acquisition. On the other hand, positive affect is necessary, but not sufficient on its own, for acquisition to take place.
Affective Factors
Affective factors relate to the learner’s emotional state and attitude toward the target language. Research on affect in language learning is still strongly influenced by Bloom’s taxonomy, which describes the affective levels of receiving, responding, valuing, organization, and self-characterization through one’s value system.
Motivation
Motivation is the psychological quality that leads people to achieve a goal. For language learners, mastery of a language may be a goal. For others, communicative competence or even basic communication skills could be a goal. In linguistics, sociolinguistics, and second-language acquisition, a number of language learner motivation models have been postulated.