Editing Cognitive categorization (section)

== Theories ==

=== Classical view ===
{{main|Categories (Aristotle)}}
The '''classical theory of categorization''', is a term used in [[cognitive linguistics]] to denote the approach to categorization that appears in Plato and Aristotle and that has been highly influential and dominant in Western culture, particularly in philosophy, linguistics and psychology.<ref name="Taylor1995ch2"/><ref>{{Cite book |last=Lakoff |first=George |title=Women, Fire, and Dangerous Things: What Categories Reveal About the Mind |publisher=University of Chicago Press |year=1987 |isbn=0-226-46803-8 |location=Chicago |oclc=14001013 |author-link=George Lakoff}}</ref>  Aristotle's categorical method of analysis was transmitted to the [[Scholasticism|scholastic]] medieval university through Porphyry's [[Isagoge]]. The classical view of categories can be summarized into three assumptions: a category can be described as a list of [[necessary and sufficient condition|necessary and sufficient]] features that its membership must have, categories are discrete in that they have clearly defined boundaries (either an element belongs to one or not, with no possibilities in between), and all the members of a category have the same status. (There are no members of the category which belong more than others).<ref name="Croft2004ch4"/><ref name="Embley2006">{{Cite book |title=Conceptual Modeling: ER 2006: 25th International Conference on Conceptual Modeling, Tucson, AZ, USA, November 6-9, 2006: proceedings |publisher=Springer |editor1=David W. Embley |editor2=A. Olivé |editor3=Sudha Ram |year=2006 |isbn=978-3-540-47227-8 |location=Berlin |oclc=262693303}}</ref>{{Page needed|date=November 2022}}<ref name="Taylor1995ch2">{{Cite book |last=Taylor |first=John R. |title=Linguistic Categorization: Prototypes in Linguistic Theory |publisher=Clarendon Press |year=1995 |isbn=0-19-870012-1 |edition=2nd |location=Oxford [England] |pages=21–24 |oclc=32546314}}</ref> In the classical view, categories need to be clearly defined, mutually exclusive and collectively exhaustive; this way, any entity in the given classification universe belongs unequivocally to one, and only one, of the proposed categories.{{citation needed|date=January 2021}}

The classical view of categories first appeared in the context of [[Western Philosophy]] in the work of [[Plato]], who, in his [[Statesman (dialogue)|Statesman]] dialogue, introduces the approach of grouping objects based on their similar [[Property (philosophy)|properties]]. This approach was further explored and systematized by [[Aristotle]] in his [[Categories (Aristotle)|Categories]] treatise, where he analyzes the differences between [[Class (philosophy)|class]]es and [[Object (philosophy)|object]]s. Aristotle also applied intensively the classical categorization scheme in his approach to the classification of living beings (which uses the technique of applying successive narrowing questions such as "Is it an animal or vegetable?", "How many feet does it have?", "Does it have fur or feathers?", "Can it fly?"...), establishing this way the basis for [[natural kind|natural]] [[Taxonomy (biology)|taxonomy]].

Examples of the use of the classical view of categories can be found in the western philosophical works of [[Descartes]], [[Blaise Pascal]], [[Spinoza]] and [[John Locke]], and in the 20th century in [[Bertrand Russell]], [[G.E. Moore]], the [[logical positivists]]. It has been a cornerstone of [[analytic philosophy]] and its [[conceptual analysis]], with more recent formulations proposed in the 1990s by [[Frank Cameron Jackson]] and  [[Christopher Peacocke]].<ref name="Pashler2012">
{{Cite book |last=Pashler |first=Harold |title=Encyclopedia of the Mind |date=2012-12-10 |publisher=SAGE Publications |isbn=978-1-5063-1938-4}}</ref><ref>{{Cite book |last=Jackson |first=Frank |url=https://academic.oup.com/book/3190 |title=From Metaphysics to Ethics: A Defence of Conceptual Analysis |date=2000-03-09 |publisher=Oxford University PressOxford |isbn=978-0-19-825061-6 |edition=1|language=en|doi=10.1093/0198250614.001.0001}}</ref><ref>{{Cite book |last=Peacocke |first=Christopher |url=https://direct.mit.edu/books/book/4676/A-Study-of-Concepts |title=A Study of Concepts |date=1995-09-25 |language=en |doi=10.7551/mitpress/6537.001.0001|isbn=9780262281317 }}</ref> At the beginning of the 20th century, the question of categories was introduced into the empirical social sciences by Durkheim and Mauss, whose pioneering work has been revisited in contemporary scholarship.<ref>{{Cite book |last1=Durkheim |first1=Emile |url=http://dx.doi.org/10.1522/cla.due.deq |title=quelques formes primitives de classification |last2=Mauss |first2=Marcel |last3=Durkheim |first3=Émile |date=2002|publisher=J.-M. Tremblay |isbn=1-55441-218-8 |series=Classiques des sciences sociales. |location=Chicoutimi|doi=10.1522/cla.due.deq }}</ref><ref>{{Cite journal |last=Alejandro |first=Audrey|date=January 2021 |title=How to Problematise Categories: Building the Methodological Toolbox for Linguistic Reflexivity|journal=International Journal of Qualitative Methods |volume=20|pages=160940692110555 |doi=10.1177/16094069211055572 |s2cid=244420443 |issn=1609-4069|doi-access=free }}</ref>

The classical model of categorization has been used at least since the 1960s from linguists of the [[structural semantics]] paradigm, by  [[Jerrold Katz]] and [[Jerry Fodor]] in 1963, which in turn have influenced its adoption also by psychologists like [[Allan M. Collins]] and [[M. Ross Quillian]].<ref name="Croft2004ch4">{{Cite book |last1=Croft |first1=William |title=Cognitive Linguistics |last2=Cruse |first2=D. Alan |publisher=[[Cambridge University Press]] |year=2004 |isbn=0521661145 |pages=74–77 |chapter=Categories, concepts, and meanings}}</ref><ref>{{Cite journal |last1=Katz |first1=Jerrold J. |last2=Fodor |first2=Jerry A. |date=1963 |title=The Structure of a Semantic Theory |url=https://www.jstor.org/stable/411200 |journal=Language |volume=39 |issue=2 |pages=170–210 |doi=10.2307/411200 |jstor=411200 |s2cid=9860676 |issn=0097-8507|url-access=subscription }}</ref>

Modern versions of classical categorization theory study how the brain learns and represents categories by [[feature detection (nervous system)|detecting the features]] that distinguish members from nonmembers.<ref>{{Citation |last1=Ashby |first1=F. Gregory |title=Chapter 7 - Multiple Systems of Perceptual Category Learning: Theory and Cognitive Tests |date=2017-01-01 |url=https://www.sciencedirect.com/science/article/pii/B9780081011072000075 |work=Handbook of Categorization in Cognitive Science (Second Edition) |pages=157–188 |editor-last=Cohen |editor-first=Henri |place=San Diego |publisher=Elsevier |language=en |doi=10.1016/b978-0-08-101107-2.00007-5 |isbn=978-0-08-101107-2 |access-date=2022-11-10 |last2=Valentin |first2=Vivian V. |editor2-last=Lefebvre |editor2-first=Claire|url-access=subscription }}</ref><ref>{{Cite journal |last1=Pérez-Gay Juárez |first1=Fernanda |last2=Thériault |first2=Christian |last3=Gregory |first3=Madeline |last4=Rivas |first4=Daniel |last5=Sabri |first5=Hisham |last6=Harnad |first6=Stevan |date=2017 |title=How and Why Does Category Learning Cause Categorical Perception? |url=https://escholarship.org/uc/item/8rg6c087 |journal=International Journal of Comparative Psychology |language=en |volume=30 |doi=10.46867/ijcp.2017.30.01.01 |issn=0889-3675|doi-access=free }}</ref>

===Prototype theory===
{{main|Prototype theory}}
The pioneering research by psychologist [[Eleanor Rosch]] and colleagues since 1973, introduced the [[prototype theory]], according to which categorization can also be viewed as the process of grouping things based on [[prototype]]s. This approach has been highly influential, particularly for [[cognitive linguistics]].<ref name="Croft2004ch4"/> It was in part based on previous insights, in particular the formulation of a category model based on [[family resemblance]] by [[Wittgenstein]] (1953), and by [[Roger Brown (psychologist)|Roger Brown]]'s ''How shall a thing be called?'' (1958).<ref name="Croft2004ch4"/>

Prototype theory has been then adopted by cognitive linguists like [[George Lakoff]]. The prototype theory is an example of a similarity-based approach to categorization, in which a stored category representation is used to assess the similarity of candidate category members.<ref name=":6">{{Cite journal |last=Reed |first=Stephen K. |date=1972-07-01 |title=Pattern recognition and categorization |url=https://dx.doi.org/10.1016/0010-0285%2872%2990014-X |journal=Cognitive Psychology |language=en |volume=3 |issue=3 |pages=382–407 |doi=10.1016/0010-0285(72)90014-X |issn=0010-0285|url-access=subscription }}</ref> Under the prototype theory, this stored representation consists of a summary representation of the category's members. This prototype stimulus can take various forms. It might be a central tendency that represents the category's average member, a modal stimulus representing either the most frequent instance or a stimulus composed of the most common category features, or, lastly, the "ideal" category member, or a caricature that emphasizes the distinct features of the category.<ref name="Kruschke, J. K. 2008">{{Citation |last=Kruschke |first=John K. |title=Models of Categorization |work=The Cambridge Handbook of Computational Psychology |pages=267–301 |year=2008 |editor-last=Sun |editor-first=Ron |series=Cambridge Handbooks in Psychology |place=Cambridge |publisher=Cambridge University Press |doi=10.1017/cbo9780511816772.013 |isbn=978-0-521-85741-3 |author-link=John K. Kruschke|doi-access=free }}</ref> An important consideration of this prototype representation is that it does not necessarily reflect the existence of an actual instance of the category in the world.<ref name="Kruschke, J. K. 2008"/> Furthermore, prototypes are highly sensitive to context.<ref>Rosch, E. (1999). Reclaiming concepts. Journal of consciousness studies, 6(11-12), 61-77.</ref> For example, while one's prototype for the category of beverages may be soda or seltzer, the context of brunch might lead them to select mimosa as a prototypical beverage.

The prototype theory claims that members of a given category share a [[family resemblance]], and categories are defined by sets of typical features (as opposed to all members possessing necessary and sufficient features).<ref>{{Cite journal |last1=Rosch |first1=Eleanor |last2=Mervis |first2=Carolyn B |date=1975-10-01 |title=Family resemblances: Studies in the internal structure of categories |url=https://dx.doi.org/10.1016/0010-0285%2875%2990024-9 |journal=Cognitive Psychology |language=en |volume=7 |issue=4 |pages=573–605 |doi=10.1016/0010-0285(75)90024-9 |s2cid=17258322 |issn=0010-0285|url-access=subscription }}</ref>

===Exemplar theory===
{{main|Exemplar theory}}
Another instance of the similarity-based approach to categorization, the exemplar theory likewise compares the similarity of candidate category members to stored memory representations. Under the exemplar theory, all known instances of a category are stored in memory as exemplars. When evaluating an unfamiliar entity's category membership, exemplars from potentially relevant categories are retrieved from memory, and the entity's similarity to those exemplars is summed to formulate a categorization decision.<ref name="Kruschke, J. K. 2008"/> Medin and Schaffer's (1978) [[Context model]] employs a [[Nearest neighbor cluster|nearest neighbor]] approach which, rather than summing an entity's similarities to relevant exemplars, multiplies them to provide weighted similarities that reflect the entity's proximity to relevant exemplars.<ref name="Medin, D. L. 1978">{{Cite journal |last1=Medin |first1=Douglas L. |last2=Schaffer |first2=Marguerite M. |year=1978 |title=Context theory of classification learning.|url=http://doi.apa.org/getdoi.cfm?doi=10.1037/0033-295X.85.3.207|journal=Psychological Review |volume=85 |issue=3 |pages=207–238 |doi=10.1037/0033-295X.85.3.207 |s2cid=27148249 |issn=1939-1471|url-access=subscription }}</ref> This effectively biases categorization decisions towards exemplars most similar to the entity to be categorized.<ref name="Medin, D. L. 1978"/><ref>Goldstone, R. L., Kersten, A., & Carvalho, P. F. (2012). Concepts and categorization. Handbook of Psychology, Second Edition, 4.</ref>

===Conceptual clustering===
{{main|Conceptual clustering}}
'''Conceptual clustering''' is a [[machine learning]] paradigm for [[unsupervised classification]] that was defined by [[Ryszard S. Michalski]] in 1980.<ref>{{cite journal
  | author = Fisher, Douglas H.
  | year = 1987
  | title = Knowledge acquisition via incremental conceptual clustering
  | journal = Machine Learning
  | volume = 2
  | pages = 139–172
  | doi = 10.1007/BF00114265
  | issue = 2| doi-access = free
  }}
</ref><ref>{{cite journal
  | author = Michalski, R. S.
  | year = 1980
  | title = Knowledge acquisition through conceptual clustering: A theoretical framework and an algorithm for partitioning data into conjunctive concepts
  | journal = International Journal of Policy Analysis and Information Systems
  | volume = 4
  | pages = 219–244}}</ref> It is a modern variation of the classical approach of categorization, and derives from attempts to explain how knowledge is represented. In this approach, [[Class (philosophy)|classes]] (clusters or entities) are generated by first formulating their conceptual descriptions and then classifying the entities according to the descriptions.<ref>{{Citation |last=Kaufman |first=Kenneth A. |title=Conceptual Clustering |date=2012 |url=http://link.springer.com/10.1007/978-1-4419-1428-6_1219 |encyclopedia=Encyclopedia of the Sciences of Learning |pages=738–740 |editor-last=Seel |editor-first=Norbert M. |place=Boston, MA |publisher=Springer US |doi=10.1007/978-1-4419-1428-6_1219 |isbn=978-1-4419-1427-9|url-access=subscription }}</ref>

Conceptual clustering developed mainly during the 1980s, as a [[machine learning|machine]] paradigm for [[unsupervised learning]]. It is distinguished from ordinary [[Cluster analysis|data clustering]] by generating a concept description for each generated category.

Conceptual clustering is closely related to [[fuzzy set]] theory, in which objects may belong to one or more groups, in varying degrees of fitness. A [[cognition|cognitive]] approach accepts that natural categories are graded (they tend to be [[fuzzy concept|fuzzy]] at their boundaries) and inconsistent in the status of their constituent members. The idea of necessary and sufficient conditions is almost never met in categories of naturally occurring things.