Editing Theory of categories (section)

==Twentieth-century development==
In the twentieth century the primacy of the division between the subjective and the objective, or between mind and matter, was disputed by, among others, [[Bertrand Russell]]<ref>Russell B. ''The Analysis of Mind'' (George Allen & Unwin, London, 1921) pp.10,23</ref> and [[Gilbert Ryle]].<ref>Ryle G. ''The Concept of Mind''  (Penguin, Harmondsworth, 1949) pp.17ff</ref> Philosophy began to move away from the metaphysics of categorisation towards the linguistic problem of trying to differentiate between, and define, the words being used. [[Ludwig Wittgenstein]]’s conclusion was that there were no clear definitions which we can give to words and categories but only a "halo" or "corona"<ref>Wittgenstein L. ''Philosophical Investigations'' 1953 (tr. Anscombe G., Blackwell, Oxford, 1978) pp.1x

X
4,181</ref> of related meanings radiating around each term. Gilbert Ryle thought the problem could be seen in terms of dealing with "a galaxy of ideas" rather than a single idea, and suggested that [[category mistake]]s are made when a concept (e.g. "university"), understood as falling under one category (e.g. abstract idea), is used as though it falls under another (e.g. physical object).<ref>Ryle G. ''Collected Papers'' (Hutchinson, London, 1971) Vol.II: ''Philosophical Arguments'' 1945, pp.201,202</ref> With regard to the visual analogies being used, [[Charles Sanders Peirce|Peirce]] and [[Clarence Irving Lewis|Lewis]],<ref>''Op.cit.1'' pp.52,82,106</ref> just like [[Plotinus]] earlier,<ref>''Op.cit.9'' VI.5.5</ref> likened the terms of propositions to points, and the relations between the terms to lines. Peirce, taking this further, talked of univalent, bivalent and trivalent relations linking predicates to their subject and it is just the number and types of relation linking subject and predicate that determine the category into which a predicate might fall.<ref>''Op.cit.5'' Vol I pp.159,176</ref> Primary categories contain concepts where there is one dominant kind of relation to the subject. Secondary categories contain concepts where there are two dominant kinds of relation. Examples of the latter were given by [[Martin Heidegger|Heidegger]] in his two propositions "the house is on the creek" where the two dominant relations are spatial location (Disjunction) and cultural association (Inherence), and "the house is eighteenth century" where the two relations are temporal location (Causality) and cultural quality (Inherence).<ref>''Op.cit.4'' pp.62,187</ref> A third example may be inferred from Kant in the proposition "the house is impressive or [[Sublime (philosophy)|sublime]]" where the two relations are spatial or mathematical disposition (Disjunction) and dynamic or motive power (Causality).<ref>Kant I. ''Critique of Judgement'' 1790 (tr. Meredith J.C., Clarendon Press, Oxford 1952) p.94ff</ref> Both [[Charles Sanders Peirce|Peirce]] and [[Ludwig Wittgenstein|Wittgenstein]]<ref>''Op.cit.25'' pp.36,152</ref> introduced the analogy of [[colour theory]] in order to illustrate the shades of meanings of words. Primary categories, like primary colours, are analytical representing the furthest we can go in terms of analysis and abstraction and include Quantity, Motion and Quality. Secondary categories, like secondary colours, are synthetic and include concepts such as Substance, Community and Spirit. 

Apart from these, the categorial scheme of [[Alfred North Whitehead]] and his Process Philosophy, alongside [[Nicolai Hartmann]] and his Critical Realism, remain one of the most detailed and advanced systems in categorial research in metaphysics.

===Peirce===
{{main|Categories (Peirce)}}

[[Charles Sanders Peirce]], who had read Kant and Hegel closely, and who also had some knowledge of Aristotle, proposed a system of merely three phenomenological categories: [[Categories (Peirce)|Firstness, Secondness, and Thirdness]], which he repeatedly invoked in his subsequent writings. Like Hegel, C.S. Peirce attempted to develop a system of categories from a single indisputable principle, in Peirce's case the notion that in the first instance he could only be aware of his own ideas. 
	"It seems that the true categories of consciousness are first, feeling&nbsp;... second, a sense of resistance&nbsp;... and third, synthetic consciousness, or thought".<ref>''Op.cit.5'' p.200, cf Locke</ref>
	Elsewhere he called the three primary categories: [[Quality (philosophy)|Quality]], Reaction and [[Meaning (semiotics)|Meaning]], and even [[Categories (Peirce)|Firstness, Secondness and Thirdness]], saying, "perhaps it is not right to call these categories conceptions, they are so intangible that they are rather tones or tints upon conceptions":<ref>''Ibid.'' p.179</ref>     
*Firstness ([[Quality (philosophy)|Quality]]): "The first is predominant in feeling&nbsp;... we must think of a quality without parts, e.g. the colour of magenta&nbsp;... When I say it is a quality I do not mean that it "inheres" in a subject&nbsp;... The whole content of consciousness is made up of qualities of feeling, as truly as the whole of space is made up of points, or the whole of time by instants".
*Secondness (Reaction): "This is present even in such a rudimentary fragment of experience as a simple feeling&nbsp;... an action and reaction between our soul and the stimulus&nbsp;... The idea of second is predominant in the ideas of causation and of statical force&nbsp;... the real is active; we acknowledge it by calling it the actual".
*Thirdness ([[Meaning (semiotics)|Meaning]]): "Thirdness is essentially of a general nature&nbsp;... ideas in which thirdness predominate [include] the idea of a sign or representation&nbsp;... Every genuine triadic relation involves meaning&nbsp;... the idea of meaning is irreducible to those of quality and reaction&nbsp;... synthetical consciousness is the consciousness of a third or medium".<ref>''Ibid.'' pp.148-179</ref>

Although Peirce's three categories correspond to the three concepts of relation given in Kant's tables, the sequence is now reversed and follows that given by [[Science of Logic|Hegel]], and indeed before Hegel of the three moments of the world-process given by [[Neoplatonism|Plotinus]]. Later, Peirce gave a mathematical reason for there being three categories in that although monadic, dyadic and triadic nodes are irreducible, every node of a higher valency is reducible to a "compound of triadic relations".<ref>''Ibid.'' p.176</ref> [[Ferdinand de Saussure]], who was developing "semiology" in France just as Peirce was developing "semiotics" in the US, likened each term of a proposition to "the centre of a constellation, the point where other coordinate terms, the sum of which is indefinite, converge".<ref>Saussure F. de,''Course in General Linguistics'' 1916 (tr. Harris R., Duckworth, London, 1983) p.124</ref>

===Others===
[[Edmund Husserl]] (1962, 2000) wrote extensively about categorial systems as part of his [[Phenomenology (philosophy)|phenomenology]].<ref>{{Cite book |last=Husserl |first=Edmund |url=https://www.worldcat.org/oclc/45592852 |title=Logical investigations |date=2001 |others=J. N. Findlay, Michael Dummett, Dermot Moran |isbn=0-415-24189-8 |edition= |location=London |oclc=45592852}}</ref><ref>{{Cite book |last=Husserl |first=Edmund |url=https://www.worldcat.org/oclc/45592852 |title=Logical investigations |others=J. N. Findlay, Michael Dummett, Dermot Moran |isbn=0415241901 |oclc=45592852}}</ref>

For [[Gilbert Ryle]] (1949), a category (in particular a "[[category mistake]]") is an important semantic concept, but one having only loose affinities to an ontological category.<ref>{{Cite book |last=Ryle |first=Gilbert |url=https://www.worldcat.org/oclc/49901770 |title=The concept of mind |date=2002 |publisher=University of Chicago Press |isbn=0-226-73296-7 |edition= |location=Chicago |oclc=49901770}}</ref>

Contemporary systems of categories have been proposed by [[John G. Bennett]] (The Dramatic Universe, 4 vols., 1956–65),<ref>{{Cite book |last=Bennett |first=John G. |url=https://www.worldcat.org/oclc/18242460 |title=The dramatic universe |date=1987 |publisher=Claymont Communications |isbn=0-934254-15-X |location=Charles Town, W. Va. |oclc=18242460}}</ref> [[Wilfrid Sellars]] (1974),<ref>{{Citation |last=deVries |first=Willem |title=Wilfrid Sellars |date=2021 |url=https://plato.stanford.edu/archives/fall2021/entries/sellars/ |encyclopedia=The Stanford Encyclopedia of Philosophy |editor-last=Zalta |editor-first=Edward N. |edition=Fall 2021 |publisher=Metaphysics Research Lab, Stanford University |access-date=2022-07-15}}</ref> [[Reinhardt Grossmann]] (1983, 1992), Johansson (1989), Hoffman and Rosenkrantz (1994), [[Roderick Chisholm]] (1996), [[Barry Smith (ontologist)]] (2003), and [[E. J. Lowe (philosopher)|Jonathan Lowe]] (2006).