The proposed paper assumes that the literary work of art is a “stratified system of norms”, and that the description of each stratum may require a different kind of logic. One of the main problems is the meaningful integration of these descriptions. A speech sound may be described on an acoustic, a phonetic and a phonemic level; normally, its acoustic description is irrelevant to its linguistic or poetic significance. However, in certain circumstances, the acoustic description may account for the emotional quality of the speech sound, may yield insight into the rhytmic structure of a poem (or just of a performance thereof), etc. Furthermore, pieces of poetry may be used to illustrate psychological theories about the aesthetic event; or psychological theories may be used to yield insight into the aesthetic nature of pieces of poetry. The paper focuses on the methodological issues involved in foregrounding the possible aesthetic significance of the transitions from one level of description to another. In doing this, it attempts to carefully navigate between two theoretical extremes: a reductionist view of literary theory according to which all the “special sciences” can be reduced to “more basic sciences” and, eventually, to physics; and the one formulated by Wellek and Warren (1956: 135) as follows: “The psychology of the reader, however interesting in itself and useful for pedagogical purposes, will always remain outside the object of literary study […] it must be unrelated either to the structure or the quality of a poem”. The middle course here proposed relies on “ the principle of marginal control”, that is, “the control exercised by the organizational principle of a higher level on the particulars forming its lower level” (Polányi, 1967: 40). Paraphrasing Polányi, the principles of literature may be said to govern the boundary conditions of a cognitive system — a set of conditions that is explicitly left undetermined by the laws of lower processes — physical, cognitive, and linguistic. If one knows more about these “lower” processes, one may get a better understanding of the principles of literature that govern those boundary conditions. It is claimed that in this way Cognitive Poetics is capable of discerning and explaining significant literary phenomena which present insurmountable difficulties to other approaches.