Levels of adequacy
Encyclopedia
In his seminal work Aspects of the Theory of Syntax (1965), Noam Chomsky
introduces a hierarchy of Levels of Adequacy for evaluating grammars (theories of specific languages) and metagrammars
(theories of grammars).
These levels constitute a taxonomy
of theories (a grammar of a natural language being an example of such a theory) according to potency. This taxonomy might be extended to scientific theories in general, and from there even stretched into the realm of the aesthetics
of art. This present article's use of the phrase as a terminus technicus should not be confused with its everyday language uses.
". This should not be confused with the application of the taxonomy in the field of aesthetics
). As a metatheory
, or "theory of theories", it becomes a concept of epistemology in the philosophy of science
, rather than a mere tool or methodology
of scientific linguistics
. As Chomsky put it in an earlier work:
Theories which do not achieve the third level of adequacy are said to "account for the observations", rather than to "explain the observations."
The second and third levels include the assumption of Ockhamist
parsimony. This is related to the Minimalist requirement, which is elaborated as a corollary
of the levels, but which is actually employed as an axiom
.
, Kant
, Carnap
, Quine
, and others. Certainly the criterion of adequacy found in rationalism
, specifically, rational empiricism
, bear some resemblance to Chomsky's formulation.
Since one of the key issues which Chomsky treats in Aspects is a supposition of a congenital endowment of the language faculty in humans, the topic ramifies into questions of innateness and a priori
knowledge, since it is by reference to those questions that the third level of adequacy is to be sought.
," which refers to Descartes' version of the ontological argument
for the existence of God in his Meditations on First Philosophy
.
Noam Chomsky
Avram Noam Chomsky is an American linguist, philosopher, cognitive scientist, and activist. He is an Institute Professor and Professor in the Department of Linguistics & Philosophy at MIT, where he has worked for over 50 years. Chomsky has been described as the "father of modern linguistics" and...
introduces a hierarchy of Levels of Adequacy for evaluating grammars (theories of specific languages) and metagrammars
Metatheory
A metatheory or meta-theory is a theory whose subject matter is some other theory. In other words it is a theory about a theory. Statements made in the metatheory about the theory are called metatheorems....
(theories of grammars).
These levels constitute a taxonomy
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
of theories (a grammar of a natural language being an example of such a theory) according to potency. This taxonomy might be extended to scientific theories in general, and from there even stretched into the realm of the aesthetics
Aesthetics
Aesthetics is a branch of philosophy dealing with the nature of beauty, art, and taste, and with the creation and appreciation of beauty. It is more scientifically defined as the study of sensory or sensori-emotional values, sometimes called judgments of sentiment and taste...
of art. This present article's use of the phrase as a terminus technicus should not be confused with its everyday language uses.
Motivation
The "potency" criterion alluded to in the preceding section is somewhat ill-defined, but may include "exhaustiveness", "effectiveness', and an affective component as well. (Arguably, the taxonomy is also motivated by considerations of "eleganceElegance
Elegance is a synonym for beauty that has come to acquire the additional connotations of unusual effectiveness and simplicity. It is frequently used as a standard of tastefulness particularly in the areas of visual design, decoration, the sciences, and the esthetics of mathematics...
". This should not be confused with the application of the taxonomy in the field of aesthetics
Aesthetics
Aesthetics is a branch of philosophy dealing with the nature of beauty, art, and taste, and with the creation and appreciation of beauty. It is more scientifically defined as the study of sensory or sensori-emotional values, sometimes called judgments of sentiment and taste...
). As a metatheory
Metatheory
A metatheory or meta-theory is a theory whose subject matter is some other theory. In other words it is a theory about a theory. Statements made in the metatheory about the theory are called metatheorems....
, or "theory of theories", it becomes a concept of epistemology in the philosophy of science
Philosophy of science
The philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...
, rather than a mere tool or methodology
Methodology
Methodology is generally a guideline for solving a problem, with specificcomponents such as phases, tasks, methods, techniques and tools . It can be defined also as follows:...
of scientific linguistics
Linguistics
Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....
. As Chomsky put it in an earlier work:
"The theory of linguistic structure must be distinguished clearly from a manual of helpful procedures for the discovery of grammars."
The levels
- Observational Adequacy
- The theory achieves an exhaustive and discrete enumeration of the data points.
- There is a pigeonhole for each observation.
- Descriptive Adequacy
- The theory formally specifies rules accounting for all observed arrangements of the data.
- The rules produce all and only the well-formed constructs (relations) of the protocol space.
"...the grammar gives a correct account of the linguistic intuition of the native speaker, and specifies the observed data (in particular) in terms of significant generalizations that express underlying regularities in the language."
- Explanatory Adequacy
- The theory provides a principled choice between competing descriptions.
- It deals with the uttermost underlying structure.
- It has predictive power.
"A linguistic theory that aims for explanatory adequacy is concerned with the internal structure of the device [i.e. grammar]; that is, it aims to provide a principled basis, independent of any particular language, for the selection of the descriptively adequate grammar of each language."
Theories which do not achieve the third level of adequacy are said to "account for the observations", rather than to "explain the observations."
The second and third levels include the assumption of Ockhamist
Occam's razor
Occam's razor, also known as Ockham's razor, and sometimes expressed in Latin as lex parsimoniae , is a principle that generally recommends from among competing hypotheses selecting the one that makes the fewest new assumptions.-Overview:The principle is often summarized as "simpler explanations...
parsimony. This is related to the Minimalist requirement, which is elaborated as a corollary
Corollary
A corollary is a statement that follows readily from a previous statement.In mathematics a corollary typically follows a theorem. The use of the term corollary, rather than proposition or theorem, is intrinsically subjective...
of the levels, but which is actually employed as an axiom
Axiom
In traditional logic, an axiom or postulate is a proposition that is not proven or demonstrated but considered either to be self-evident or to define and delimit the realm of analysis. In other words, an axiom is a logical statement that is assumed to be true...
.
Precursors in the philosophy of science
It is suggested that the system of levels proposed by Chomsky in Aspects of the Theory of Syntax has its antecedents in the works of DescartesRené Descartes
René Descartes ; was a French philosopher and writer who spent most of his adult life in the Dutch Republic. He has been dubbed the 'Father of Modern Philosophy', and much subsequent Western philosophy is a response to his writings, which are studied closely to this day...
, Kant
Immanuel Kant
Immanuel Kant was a German philosopher from Königsberg , researching, lecturing and writing on philosophy and anthropology at the end of the 18th Century Enlightenment....
, Carnap
Rudolf Carnap
Rudolf Carnap was an influential German-born philosopher who was active in Europe before 1935 and in the United States thereafter. He was a major member of the Vienna Circle and an advocate of logical positivism....
, Quine
Willard Van Orman Quine
Willard Van Orman Quine was an American philosopher and logician in the analytic tradition...
, and others. Certainly the criterion of adequacy found in rationalism
Rationalism
In epistemology and in its modern sense, rationalism is "any view appealing to reason as a source of knowledge or justification" . In more technical terms, it is a method or a theory "in which the criterion of the truth is not sensory but intellectual and deductive"...
, specifically, rational empiricism
Empiricism
Empiricism is a theory of knowledge that asserts that knowledge comes only or primarily via sensory experience. One of several views of epistemology, the study of human knowledge, along with rationalism, idealism and historicism, empiricism emphasizes the role of experience and evidence,...
, bear some resemblance to Chomsky's formulation.
Since one of the key issues which Chomsky treats in Aspects is a supposition of a congenital endowment of the language faculty in humans, the topic ramifies into questions of innateness and a priori
A priori and a posteriori (philosophy)
The terms a priori and a posteriori are used in philosophy to distinguish two types of knowledge, justifications or arguments...
knowledge, since it is by reference to those questions that the third level of adequacy is to be sought.
Note
This concept should not to be confused with the "causal adequacy principleCausal adequacy principle
The "causal adequacy principle" is a philosophical claim made by René Descartes that the cause of an object must contain at least as much reality as the object itself, whether formally or eminently....
," which refers to Descartes' version of the ontological argument
Ontological argument
The ontological argument for the existence of God is an a priori argument for the existence of God. The ontological argument was first proposed by the eleventh-century monk Anselm of Canterbury, who defined God as the greatest possible being we can conceive...
for the existence of God in his Meditations on First Philosophy
Meditations on First Philosophy
Meditations on First Philosophy is a philosophical treatise written by René Descartes and first published in 1641 . The French translation was published in 1647 as Méditations Metaphysiques...
.
External links
- Boeckx, Cedric, and Norbert Hornstein.The Varying Aims of Linguistic Theory. Online version at
- http://kybele.psych.cornell.edu/LU/Hornstein-Paris-final_1.pdf, accessed 2006-04-19.