Against Comprehensible Input: the Input Hypothesis and the Development of Second-language Competence

S. D. Krashen argues that language acquisition is caused by learners understanding input which is slightly beyond their current stage of knowledge, by means of context and other extra-linguistic cues, and that, while we should not try to provide input which specifically aims at the next stage, 'comprehensible' input is particularly beneficial. In this article I will suggest that there are a number of problems with Krashen's input hypothesis, as currently formulated. Firstly, by concentrating on meaning and context, he misses the fact that certain aspects of grammar development in the learner are largely internally driven, and independent of context or meaning. Secondly, he overestimates the role and benefits of simplified input. Thirdly, Krashen feels that we can never really be sure what input is relevant to what stage, but this is due to the imprecision of his formulation: once one incorporates a detailed theory of language, it is possible to come up with a theory to identify precisely what aspects of input trigger development. Finally, there are circumstances where the secondlanguage (L2) input will not be able to show the learner how to retreat from certain non-target forms: the input hypothesis is geared to handling additions to intermediate grammars, rather than losses. I will argue that second-language acquisition theory should indeed include an input hypothesis, and, consequently, that we should try and tighten up Krashen's formulation to deal with these objections, rather than abandoning it.