1. Introduction: Input versus Output. A general overview
In order to assess how compatible Krashen’s and Swain’s views are, it is essential to first outline the basics of each view, that is, the main tenets of their hypotheses.
As part of his Monitor Model, Krashen (1981,1982, 1985) formulated the Input Hypothesis, which claims that language input (listening and reading comprehension) constitutes the main communicative process through which we acquire a second language. Krashen believes that fluency in speaking or writing in a second language will naturally come about after learners have built up sufficient competence through comprehending input. However, it is not just any kind of input that is appropriate or effective, or as Krashen puts it, not all input will produce intake. The term “intake” is closely linked to how affective factors affect second language acquisition (SLA from now on), and this is how this author refers to the amount of input that is effectively assimilated by the learner. In such direction, he stated that it was only “comprehensible input” which would be effective for SLA. Such input is the one which is only slightly above the current level of the learner’s competence, which he represented with the simple formula I + 1, where I = input. This input is made comprehensible because of the help provided by the context. Thus, if the learner receives understandable input, language structures will be naturally acquired, according to Krashen. Therefore, the ability to communicate in a second language will emerge as a consequence of comprehensible input. Moreover, as part of his Affective Filter Hypothesis, previously put forward by Dulay and Burt (1977), Krashen argues that learners are not to be forced to produce language, as this would bring about a considerable amount of anxiety, which would cause them to develop a high affective filter that would prevent them from acquiring the target language smoothly.
In opposition to Krashen’s Input Hypothesis lies the Output Hypothesis, issued by Swain (1985). In contrast to the former, Swain’s hypothesis proposes that it is through language production (written or spoken) that SLA may be more likely to occur. This is so because, as claimed by its author, it is during language production stages that learners realise what they know and what they don’t. This may happen when a learner is trying to convey a message but his or her linguistic knowledge of the second language is insufficient to do so. It is then that the learner realises that s/he ignores some useful language structures and/or words needed to express a desired message. This issue is what Swain refers to as the “gap” between what one can say and what one would like to be able to say. And it would be on realizing this gap, that learners are motivated towards modifying their output in order to learn something new about the target language. Besides, this hypothesis asserts that language production aids learners in four different ways (Swain, 1993). The first derives from the fact that language production provides opportunities for meaningful practice, allowing the development of automatic linguistic behaviours. The second is related to that which forces the learner to switch from semantic mental processes to syntactic ones. As Krashen (1982) suggested: “In many cases, we do not utilize syntax in understanding, we often get the message with a combination of vocabulary, or lexical information plus extra-linguistic information”. Whereas in an understanding process the use of syntax may not be essential, it is in the production stages that learners are forced to consider syntactic aspects of the target language.
The third way in which language production helps learners in acquiring a L2 is through testing hypotheses, since output provides students with the opportunity to test their own hypotheses, and withdraw their own conclusions. This third aspect is closely related to the fourth one, which deals with the responses of other speakers of the language, especially native ones, which can give learners information on how comprehensible or well-formed their utterances are.
It must be said that, despite all emphasis being laid on output, Swain admits that output is not solely responsible for SLA.
To sum up, where Krashen sees input hugely responsible for language acquisition, Swain considers output; where the latter claims language production to be of utter importance, the former regards it as not necessary, as something that should not be forced, since it will appear naturally after a certain amount of comprehensible input.
Before continuing with this article, it must be noted that no distinction between the terms “learning” and “acquisition” is being made, as most authors do not consider it amongst their theories of SLA.
2. Input and Output: rejecting or complementing each other?
In this section we will be looking at how the terms input and output have been dealt with by other authors, and whether these support either Krashen’s or Swain’s views of SLA, and in what Language of desire ways they do so. We will also consider if these two concepts are opposites or simply two sides of the same coin.
Originated by the work of Chomsky (1957), the Generative Paradigm arose as a clear opposition to the structural approach to linguistics. And, although this paradigm did not deal with how languages were learned, it did however consider the term output within one of its main features, given the importance of the creative nature of language use within this paradigm. It is here where output is first remotely considered, as creativity calls for production and this may be understood as the very core of output. Moreover, according to Chomsky, creativity has to come hand in hand with compliance to rules, as any type of creation ought to take part within a framework governed by a set of rules. It is here where Swain’s hypothesis may receive support, since she believes that production leads learners to consider syntax as such, which can be considered as that set of rules which governs a particular communicative framework.
Moving now towards the field of SLA specifically, we find three different theories that aim at explaining how language is acquired, and these are the behaviourist, nativist and interactionist theories. We will focus firstly on behaviourist and nativist views.
As far as behaviourism is concerned, a language is learned by the creation of a series of habits which are acquired by imitation. Thus, we can find both input and output in this theory, since learners imitate (output) something that has previously been assimilated (input). As regards nativist theories, while learning a language, learners are constantly forming hypotheses based on the information received (input). However, they also test these hypotheses through speech (output) and comprehension (input).
So we can see how, within behaviourist theories, output is considered as imitation, which accounts for Swain’s argument related to the creation of automatic linguistic behaviours. From a nativist point of view, the Output Hypothesis is also backed, since it would be through speech that learners test what they know and what they don’t. In the same way, both behaviourist and nativist theories stand beside Krashen’s Input Hypothesis, as they both explicitly consider output to be a natural consequence of input. So it is at this point that we can see how these two seemingly opposite hypotheses start complementing rather than denying each other’s validity.