ABSTRACT
As perhaps in all areas of human knowledge, in the field of applied linguistics nothing ever happens in a vacuum. New ideas do not just spring out of thin air; they often come out of old ideas, and from ideas in other areas of knowledge. In this chapter we shall look into the background of two sets of ideas which have had a great deal of influence on the direction of foreign-language learning and teaching studies. These ideas are not easy ones to grasp, and for this reason you may find this chapter the most challenging of the book. But understanding the ideas and where they come from really will enrich your insight into the field.
