Optimality Theory (OT)

Prepared and presented by :

Abdullah Bosaad & 刘畅 Liú Chàng

Spring 2011

-OT started around 1990 when Alan Prince and Paul

Smolensky wrote

a book-length manuscript called Optimality Theory: Constraint

Interaction in Generative Grammar, which had a terrific

impact on the field of linguistics.

-According to McCarthy, OT is considered one of the top three

developments in the history of generative grammar. (2008)

-OT shows how certain constraints interact with each other, and how this

interaction leads to the best well-formed candidate .

-In OT, the higher-priority constraint dominates the lower-priority

constraint.

-OT is inherently comparative; no output “candidate” is good or bad by

itself. It’s only good or bad in relation to other candidates from the same

input .

-Language X has the following two constraints with higher-priority to (a),

and lower-priority to (b) :

a) only clusters that consist of two consonants are allowed

b) no final vowel is allowed.

Which one of the following outputs “candidates” could be the winner?

1[ (klasta[ , ]klastus]

2[ (mgtesk[ ,]mtesku ]

1 (The constraints themselves are universal

2 (All constraints are present in the grammar of all languages

(phonology and syntax). However, constraints ranking is the only

systematic difference among languages .

In OT, constraints are divided into two kinds:

a) Faithfulness Constraints: impose the exact preservation of the

input in the output (i.e. prohibit differences between input and output).

Ex. “Dep” = output depends on input

b) Markedness constraints: impose conditions on the well-

formedness of the output .

Ex. *C unsyll = no unsyllabified cons/ no consonant stays by itself in

a syllable

1 (GEN (Generator): provides the list of possible outputs “candidates” for a given input:

/input/ GEN {list of outputs}

2 (CON (Constraints)

3 (EVAL (Evaluator): its job is to find the optimal candidate:/input/ GEN {list of outputs} CON EVAL ]the optimal output[

-An objection to optimality theory is the claim that it is not technically a theory, in that it does not make falsifiable predictions. The source of this

issue is terminology; the term "theory.“

-Optimality theory is also criticized as being an impossible model of speech production/perception: computing and comparing an infinite number of possible candidates would take an infinitely long time to process .

It is impossible to make a direct ranking argument when constraints are in a “stringency relation” or “general-specific relation”

)when every violation of CONST2 is also a violation of CONST1, but not vise versa (

EX .

a. IDENT (]voice[) assign one violation mark for every output segment that differs from its input correspondent in the feature ]voice[.

b. IDENT onset (]voice[) assign one violation mark for every output segment in syllable onset position that differs from its input correspondent in the feature ]voice[ .

-What happens when two outputs tie on all the constraints that have been considered so far ?

CONST1CONST2CONST3

cand1**

cand2**

CONST1CONST2CONST3CONST4

cand1**

cand2***