In generative linguistics, Distributed Morphology is a theoretical framework introduced in 1993 by Morris Halle and Alec Marantz.[1] 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.
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 in the sense it has in traditional generative grammar. Distributed Morphology rejects the notion of a lexicon in the way it had been used. Any operation that would occur in the 'lexicon' according to lexicalist approaches is considered too vague in Distributed Morphology, which instead distributes these operations over various steps and lists.[2] 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.[3] In contrast to lexicalist models of morphosyntax, Distributed Morphology posits three components in building an utterance:
There are three relevant lists in Distributed Morphology: the Formative List, the Exponent List (Vocabulary Items), and the Encyclopedia. Items from these lists enter the derivation at different stages.
The formative list, sometimes called the lexicon (this term will be avoided here) in Distributed Morphology includes all the bundles of semantic and sometimes syntactic features that can enter the syntactic computation. These are interpretable or uninterpretable features (such as [+/- animate], [+/- count], etc.) 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, that is after all syntactic operations are over. The Formative List in Distributed Morphology differs, thus, from the Lexicon in traditional generative grammar, which includes the lexical items (such as words and morphemes) in a language.
As its name would suggest, 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.[4] 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.[5] 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.
As of 2020, there is no consensus on which approach most accurately describes the structural configuration of root categorization.
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 known from generative grammar.[10] Postsyntactic Morphology posits that this operation takes place after the syntax itself has occurred.
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.[11] In other words, a vocabulary item is a relation between a phonological string (which could also be zero or null) and the context in which this string may be inserted.[12] Vocabulary items compete for insertion to syntactic nodes at spell-out, i.e. after syntactic operations are complete. The following is an example of a vocabulary item in Distributed Morphology:
An affix in Russian can be exponed as follows:
/n/ <--> [___, +participant +speaker, plural][13] 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:
[+1 +sing +nom +prn] ←→ /aj/[+1 +sing +prn] ←→ /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 [+nom], 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(E1) ⊂ f(T), f(E2) ⊂ f(T), and f(E1) ⊂ f(E2) → f(E2) wins.[14]
In this case, both /mi/ and /aj/ have a subset of features f(T), but /aj/ has the maximal subset.
The Encyclopedia associates syntactic units with special, non-compositional aspects of meaning.[10] This list specifies interpretive operations that realize in a semantic sense the terminal nodes of a complete syntactic derivation. For example, adjectives compárable and cómparable are thought to represent two different structures. First one, has a composition meaning of ‘being able to compare’ – root combines with a categorizer V- and the two combine with the suffix –able. The second one has an idiomatic meaning of ‘equal’ taken directly from the Encyclopedia – here root combines directly with the suffix –able.
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:
The phonological exponent of a Vocabulary Item is inserted into a morpheme in the terminal string if the item matches all or a subset of the grammatical features specified in the terminal morpheme. Insertion does not take place if the Vocabulary item contains features not present in the morpheme. Where several Vocabulary items meet the conditions for insertion, the item matching the greatest number of features specified in the terminal morpheme must be chosen.[13]
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.[10] For example, Embick and Noyer (2001)[15] argue that Lowering applies before Vocabulary insertion, while Local Dislocation applies afterwards.
Apart from the operations described above, some researchers (Embick 1997 among others)[16] 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".
Morphological Merger is generalized as follows in Marantz 1988: 261:
Morphological Merger:
At any level of syntactic analysis (d-structure, s-structure, phonological structure), a relation between X and Y may be replaced by (expressed by) the affixation of the lexical head of X to the lexical head of Y.[17]
Two syntactic nodes can undergo Morphological Merger subject to morphophonological well-formedness conditions.[10]
Two nodes that have undergone Morphological Merger or that have been adjoined through syntactic head movement can undergo Fusion, yielding one single node for Vocabulary insertion.[10] Many-to-one relation where two syntactic terminals are realized as a single exponent (portmanteau).[18]
An example can be found in Swahili, which has separate exponents for subject agreement (e.g., 1st plural tu-) and negation (ha-):
However, 1st person singular exponent ni- and negation ha- undergo fusion and realized as si-:
An alternative analysis of si- exponent says that there is no fusion but rather context sensitive allomorphy:
Fission refers to the splitting of one terminal node into two distinct terminal nodes prior to Vocabulary Insertion. Some of the most well-known cases of fission involve the imperfect conjugations of Semitic, in which agreement morphology is split into a prefixal and suffixal part, as investigated in the work of Noyer (1992).[19] Fission may also occur where insertion of a Vocabulary item discharges the intrinsic features of the Vocabulary item from the terminal node, leaving others features available for possible insertion; if fission applies, then other Vocabulary items can be inserted to discharge the remaining features. When Fission occurs, the order of morphemes is influenced by the featural complexity of Vocabulary items.[20]
Impoverishment (a term introduced into the theory in Bonet 1991) refers to a change in the feature content on a terminal node prior to Vocabulary Insertion, resulting in a less marked feature content.