Generative metrics

Generative metrics is the collective term for 3 distinct theories of verse structure (focusing on the English iambic pentameter) advanced between 1966 and 1977. Inspired largely by the example of Noam Chomsky's Syntactic Structures (1957) and Chomsky and Morris Halle's Sound Pattern of English (1968), these theories aim principally at the formulation of explicit linguistic rules that will generate all possible well-formed instances of a given meter (e.g. iambic pentameter) and exclude any that are not well-formed. "All three [theories] have undergone major revision, so that each exists in two versions, the revised version being preferable to the original in every case."

The earliest (and most-discussed) theory of generative metrics is that put forth by Morris Halle and Samuel Jay Keyser — first in 1966 with respect to Chaucer's iambic pentameter, and in its full and revised form in 1971's English Stress: Its Forms, Its Growth, and Its Role in Verse. Halle and Keyser conceive of the iambic pentameter line as a series of (nominally) 10 Weak and Strong positions:

but to accommodate acephalous lines, and feminine and triple endings, use this full formulation:

where the first Weak position is optional, and the final 2 positions (which must be unstressed) are also optional. They then define their signal concept, the Stress Maximum, as a stressed syllable "located between two unstressed syllables in the same syntactic constituent within a line of verse". Finally, the fit between syllables and the positions they occupy are evaluated by these 2 hierarchical sets of correspondence rules:

(i) A position (S or W) corresponds to either

AND

(ii)

Rules are evaluated in order. If rules (i)-1 or (ii)-1 or (ii)-2 are broken, this indicates increasing complexity of the line. But if (i)-2 or (ii)-3 are broken, the line is unmetrical. (Note that some sources erroneously state that the presence of a Stress Maximum makes a line unmetrical; this is false. In Halle & Keyser's theory a Stress Maximum in a W position makes a line unmetrical.)

An example of Halle and Keyser's scansion is:

Stresses are indicated by a slash "/" and Stress Maxima by "M". A single underline indicates a violation of (ii)-1; a double underline indicates a violation of (ii)-1 & 2. In addition, the Stress Maximum "lap", since it occurs on a W position, violating (ii)-3, should get a third underline, rendering the line unmetrical. (Because of display limitations, this is here indicated by striking out the "M".)

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