Accounting for Multiple Degrees of Stress

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6. Toward a Unified Theory of Prosody

The preceding chapters laid out the theoretical motivation as well as a broad base of empirical support for the autosegmental theory of stress. The aims of this final chapter are threefold. First, section 6.1 suggests how the proposed theory might be extended to account for two types of phenomena which were mentioned only briefly in chapter 2. These are i. multiple degrees of stress, and ii. “long range” stress shift under clash, as in the English Rhythm Rule. Next, section 6.2 discusses a potential objection to the autosegmental theory of stress. This concerns the observation that stress autosegments never seem to undergo the autosegmental process of spreading. It is suggested, as a preliminary explanation, that stress cannot undergo spreading because to do so would conflict with its central function in setting off one element in a representation as more prominent than all the others. The final aim of this chapter, which is covered in section 6.3, is to present a brief synopsis of the autosegmental theory of stress. I begin with a discussion of how the theory proposed in chapter 2 might be extended to account for the existence of multiple degrees of stress within a single domain.

6.1. Accounting for Multiple Degrees of Stress

Although the focus of this study has been the development of a theory of stress placement, chapter 2 briefly mentioned two types of phenomena which imply the existence of some kind of hierarchical relationship between individual stresses. One of these is the occurrence of multiple degrees of stress in a large number of languages. The other phenomenon might be referred to as “long range” stress shift. Section 2.2.1 discussed the English Rhythm Rule as an example of this. In this section I suggest how the autosegmental theory of stress might be extended in order to account for these two sets of phenomena. Looking first at the occurrence of multiple degrees of stress, how might the autosegmental theory of stress be extended or augmented in order to account for this phenomenon? Before attempting to answer this question, consider how the theories of Hayes, Hammond, and HV have handled multiple degrees of stress. Since each of these theories views the foot as a grouping of abstract terminal elements, one of which has to be a head, it is quite natural for the heads of feet to themselves be grouped into super-feet, also known as cola Stowell 1979; Hammond 1987a or word trees Hayes 1981. One of the members of each colon or word tree is then designated as the head using the same kinds of devices that are available for designating one of a foot’s terminal elements as the head of that foot. This process, which may be repeated for as many levels as necessary in order to derive all of the observed degrees of stress, was illustrated in section 1.2.2. The same basic approach may be applied to stressed feet that have been derived under my proposal. The only difference is that feet are headless in my theory, so it is not possible to group heads into cola. Instead, the stresses themselves must be grouped into cola. A stress autosegment is then inserted and linked on a higher line in each colon. The docking point in this case is a foot-level stress autosegment, and the direction of linking may or may not be the same as the direction of linking of the foot-level stress. This is illustrated schematically in 371. 371 | | | õ õõ õ Example: Mìssissíppi Higher-level cola may subsequently be built in order to create as many degrees of stress as needed. Following the theories of Hammond 1987a and HV, I assume that the phonetic distinctions between the various degrees of stress are generated during phonetic implementation. Next, consider how this approach might be used to account for the case where stress shifts under clash to a stress-bearing unit which is not adjacent to the stress-bearing unit that it shifted from. Section 2.2.1 cited the English Rhythm Rule Chomsky and Halle 1968; Liberman and Prince 1977; Kiparsky 1979; Prince 1983; Hayes 1984; Halle and Vergnaud 1987b; Hammond 1988a as an example of such a phenomenon. A sample set of the relevant facts is repeated in 372 to 374 from section 2.2.1. The basic observation is that the leftmost of two primary stresses moves leftward to the site of a formerly subsidiary stress when the two primary stresses occur on adjacent syllables in certain phrase-level contexts. 372 a. Tènnessée b. Ténnessèe Wílliams 373 a. Mìssissíppi b. Míssissìppi Ríver 374 a. Àpalàchicóla b. Ápalàchicòla Árnie Three observations should be noted about 372 through 374. First, unlike the movement under clash that occurs in Italian section 2.2.1, the movement in this case is “long distance” in the sense that it skips one or more intervening stress-bearing units. Second, the movement is not to a formerly stressless position but rather to a position which already bore non-primary stress. Third, the position from which primary stress moves does not become stressless. Rather, it acquires a non-primary stress. Thus, the Rhythm Rule has the effect of “swapping” the positions of a primary and a non-primary stress in order to resolve a clash between two primary stresses within a phrase. The model in 371 may be used to derive the English Rhythm Rule as follows. First, the output of all lexical stress assignment rules is derived by building cola on top of foot-level i.e., line 1 stresses, as shown in 375. 375 Output of Lexical Rules: | | | | | õ õ õ õ õ õ | | | | | | [M iss iss ipp i] [R i v er] [Mìssissíppi] ... [Ríver] Next, Bracket Erasure i.e., entering the post-lexical phase results in an OCP violation in that two tokens of line 2 are linked to adjacent tokens of line 1 . This is resolved by delinking the leftmost line 2 and relinking it from left to right to the first potential anchor, which is the leftmost token of line 1 . The resulting representation is illustrated in 376. 376 Output of Clash Resolution: | | | | | õ õ õ õ õ õ | | | | | | M iss iss ipp i R i v er Míssissìppi Ríver Thus, the English Rhythm Rule may be derived by building super-feet or cola which consist only of autosegmental stresses and then directionally linking a second stress autosegment on line 2 in each super-foot. The OCP forces the leftmost of two adjacent line 2 stresses to delink; it then relinks to the leftmost line 1 stress. It is possible that other approaches would also be compatible with the theory of stress that has been proposed in this study; I leave this as an area for future research. In conclusion, the existence of multiple degrees of stress within a single domain does not pose a problem for the autosegmental theory of stress, nor does the English Rhythm Rule pose a problem. In both cases I follow the theories of Hammond 1987a and HV in constructing super-feet from lower level stresses. Next, I discuss the autosegmental process of spreading and its relationship to the autosegmental theory of stress. 6.2. Can Stress Spread?