We can intepret the rough outline of the history of literary criticism in terms of Jakobson's figure. Each period has tended to consider that the essence of the literary phenomenon, or the proper object of study of literary theory, is located in some element or other of the communicative situation. Of course all elements are present at all times in actual literary practice, and some degree of attention is given to all at all times, but somehow one of them reaches a prominence which makes it seem the really important one, the key to the secret of literature. From a semiotic point of view we must be concerned with all at all times, but we can't ignore the fact that different importance is given to them by the critics we will be studying.