Distributed morphology


In generative linguistics, Distributed Morphology is a theoretical framework introduced in 1993 by Morris Halle and Alec Marantz. The central claim of Distributed Morphology is that there is no divide between the construction of words and sentences. The syntax is the single generative engine that forms sound-meaning correspondences, both complex phrases and complex words. This approach challenges the traditional notion of the lexicon as the unit where derived words are formed and idiosyncratic word-meaning correspondences are stored. In Distributed Morphology there is no unified lexicon, as in earlier generative treatments of word-formation; rather, the functions that other theories ascribe to the lexicon are distributed among other components of the grammar.

Overview of Distributed Morphology

The basic principle of Distributed Morphology is that there is a single generative engine for the formation of both complex words and complex phrases: there is no division between syntax and morphology, and there is no lexicon—at least, not in the same sense as in traditional generative grammar. Any operation that would—according to lexicalist approaches—occur in the 'lexicon' is considered too vague in Distributed Morphology, which instead distributes these operations over various steps and lists.
The term 'Distributed Morphology' is used because the morphology of an utterance is the product of operations distributed over more than one step, with content from more than one list. In contrast to lexicalist models of morphosyntax, Distributed Morphology posits three components in building an utterance:
  1. The Formative List provides the input for syntax.
  2. The Exponent List is consulted to provide the utterance with post-syntactic phonological content.
  3. Syntactic operations apply to formatives.
An additional list, the 'Encyclopedia', provides for the realization of non-compositional—idiomatic—meanings. Items from these lists enter the derivation at different stages.

Formative list: category-neutral roots

The formative list, sometimes called the lexicon, includes all the bundles of semantic and sometimes syntactic features that can enter the syntactic computation. These are interpretable or uninterpretable features which are manipulated in syntax through syntactic operations. These bundles of features do not have any phonological content; phonological content is assigned to them only at spell-out—i.e., after all syntactic operations are completed. The formative list thus differs from the lexicon, which includes the lexical items—such as words and morphemes—in a language.
As its name suggests, the formative list contains what are known as formatives, or roots. In Distributed Morphology, roots are proposed to be category-neutral and undergo categorization by functional elements. Roots have no grammatical categories in and of themselves, and merely represent the bundle of semantic features to be exponed. The notation for roots in Distributed Morphology generally uses a square root symbol, with an arbitrary number or with the orthographic representation of the root. For example, love, without a grammatical category, could be expressed as √362 or as √LOVE.
Researchers adopting the Distributed Morphology approach agree that roots must be categorized by functional elements. There are multiple ways that this can be done. The following lists four possible routes.
  1. Roots are merged as complements to the functional elements that categorize them.
  2. Roots are merged as modifiers to the functional elements that categorize them.
  3. Some roots are merged as modifiers and others as complements to the function elements that categorize them.
  4. Roots are inserted post-syntactically and do not merge with complements or modifiers.
As of 2020, there is no consensus on which approach most accurately describes the structural configuration of root categorization.

Exponent list: vocabulary items

Vocabulary items associate phonological content with arrays of underspecified syntactic and/or semantic features—the features listed in the lexicon—and they are the closest notion to the traditional morpheme concept as known from generative grammar. Postsyntactic Morphology posits that this operation takes place after the syntax itself has been expressed.
Vocabulary items are also known as the exponent list. In Distributed Morphology, after the syntax of a given utterance is complete, the exponent list must be consulted to provide phonological content. This is known as 'exponing' an item. In other words, a vocabulary item is a relation between a phonological string and the context in which this string may be inserted. Vocabulary items compete for insertion to syntactic nodes at spell-out, i.e. after syntactic operations are complete.
As an example of a vocabulary item, an affix in Russian can be exponed as follows:
/n/ ←→
The phonological string on the left side is available for insertion to a node with the features described on the right side.
Roots, i.e. formatives from the formative list, are exponed based on their features. For example, the first-person singular pronominal paradigm in English is exponed as follows:
←→ /aj/
←→ /mi/
The use of /mi/ does not seem infelicitous in a nominative context at first glance. If /mi/ acquired nominative case in the syntax, it would seem appropriate to use it. However, /aj/ is specified for the feature , and therefore must block the use of /mi/ in a nominative context. This is known as the Maximal Subset Condition or the Elsewhere Principle: if two items have a similar set of features, the one that is more specific will win. Illustrated in logical notation:
  • f ⊂ f, f ⊂ f, and f ⊂ f → f wins.
In this case, both /mi/ and /aj/ have a subset of features f, but /aj/ has the maximal subset.

Encyclopedia

The Encyclopedia associates syntactic units with special, non-compositional aspects of meaning. This list specifies interpretive operations that realize, in a semantic sense, the terminal nodes of a complete syntactic derivation. For example, the adjectives compárable and cómparable are thought to represent two different structures: the former has a compositional meaning of ‘being able to compare’ ; the latter has an idiomatic meaning of ‘equal’ taken directly from the Encyclopedia.

Derivation

The Y-model of Minimalism, as well as the syntactic operations postulated in Minimalism, are preserved in Distributed Morphology. The derivation of a phrase/word proceeds as follows:
  1. A subset of the formative list—i.e., some combination of interpretable and uninterpretable features—and category-neutral lexical roots enter the computation. These features specify structural relations, which are satisfied via the operation of syntactic operations such as Merge, Move or Agree. For example, if node A has a feature, while node B has no value assigned to the feature , then node B could become if it is in the right configuration with node A for Agree to apply. The category-neutral roots combine with a categorizer, e.g. N-, A-, or V-, and turn into—respectively—a category noun, adjective or verb. Once all relations specified by the features present in the numeration are satisfied, the syntactic derivation is complete; there is a configuration of terminal nodes and roots, but without phonological content assigned to these nodes. At spell-out, the traditional division into logical form and phonetic form of the Y-model takes place.
  2. At LF, the encyclopedia is responsible for the semantic interpretation of the terminal nodes. Any non-compositional and idiosyncratic meaning associated with the bundles of features and lexical roots present at the end of the syntactic computation is assigned at this stage.
  3. After syntactic operations are complete, certain morphological operations apply before any assignment of phonological content to the terminal nodes.
  4. Once these morphological operations are complete, phonological content is finally assigned to the terminal nodes, through competition of vocabulary items for insertion: each terminal node contains a bundle of features, and all vocabulary items compete for insertion into the terminal nodes; the vocabulary item that wins the competition, and so is inserted in a certain terminal node, is the item that is most highly specified for that node. For example, if—at the end of the derivation—there is a terminal node with the features and the lexical root √PLAY, then the phonological content that will be assigned to the node will be the one corresponding to "played": the most highly specified vocabulary item for this node is the item /d/ ←→ . It is important to note that this vocabulary item does not exactly match the features of the terminal node; however, it wins the competition because in English it is the most highly specified vocabulary item for the specific values of features present in the node. Competition for insertion is governed by the Subset Principle, the following version of which is from Halle :

    Morphological operations

Distributed Morphology recognizes a number of morphology-specific operations that occur post-syntactically. There is no consensus about the order of application of these morphological operations with respect to vocabulary insertion, and it is generally believed that certain operations apply before vocabulary insertion, while others apply to the vocabulary items themselves. For example, Embick and Noyer argue that Lowering applies before Vocabulary insertion, while Local Dislocation applies afterwards.
Apart from the operations described above, some researchers have suggested that there are morphemes that represent purely formal features and are inserted post-syntactically but before spell-out: these morphemes are called "dissociated morphemes".