T HE great popularity of audio-lingual methods in second-language teaching today is more than just an over-reaction to previous pedagogic techniques that concentrated almost exclusively on reading, translation, and composition skills, and neglected oral comprehension and speaking ability. In large part, it is also a reflection of the widespread cultural belief that children learn languages much more readily than adults' do. Hence, the argument runs, if children achieve such spectacular success by means of an audio-lingual approach, it must obviously be the most effective way of learning foreign languages, and adults should follow their example. This line of argument, in my opinion, is vulnerable on two counts. In the first place, on either research or theoretical grounds, it is difficult to substantiate the thesis that children are in fact superior to adults in learning languages. Second, even if this were the case, there would still be no good reason for believing that methods which yield satisfactory results with children must necessarily be appropriate for adults. These latter methods are used, after all, not because they are demonstrably more efficacious under all conditions, but because children's cognitive immaturity and lack of certain intellectual skills preclude many approaches that are feasible for older age groups. Naturalness is a slippery argument because what is natural for one age group is not necessarily natural for another.