]> 2008/06/10 OpenCyc Knowledge Base Copyright© 2001-2008 Cycorp, Inc., http://www.cyc.com/, Austin, TX, USA This file contains an OWL representation of information contained in the OpenCyc Knowledge Base. The content of this OWL file is licensed under the Creative Commons Attribution 3.0 license whose text can be found at http://creativecommons.org/licenses/by/3.0/legalcode. The content of this OWL file, including the OpenCyc content it represents, constitutes the "Work" referred to in the Creative Commons license. The terms of this license equally apply to, without limitation, renamings and other logically equivalent reformulations of the content of this OWL file (or portions thereof) in any natural or formal language, as well as to derivations of this content or inclusion of it in other ontologies. externalID A unique, language-neutral, variable-sized identifier for a concept that can be used to refer unambiguously to that concept across OWL exports or across Cyc inference engines. label A natural-language representation for a concept that is both human readable and readable by the Cyc inference engine. These terms are not guaranteed to refer to the same concept across time but are guaranteed to be consistent within a particular OWL export. Use 'cycAnnot:externalID' for unambiguously referring to a concept across OWL exports or across Cyc inference engines. An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> (q.v.). <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv7LKYpwpEbGdrcN5Y29ycA" class="cyc_term">Nothing</a> is in effect the collection-theoretical complement of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> (q.v.): the necessarily empty collection that is by definition equal to (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwTvAxJwpEbGdrcN5Y29ycA" class="cyc_term">rewriteOf</a>) (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwROrhZwpEbGdrcN5Y29ycA" class="cyc_term">CollectionDifferenceFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>). non-thing Nothing http://en.wikipedia.org/wiki/Nothing non-things thing that is not something the empty set TheEmptySet <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvfjtrpwpEbGdrcN5Y29ycA" class="cyc_term">TheEmptySet</a> is the empty (or "null") set: the unique set that has no elements. Note that <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvfjtrpwpEbGdrcN5Y29ycA" class="cyc_term">TheEmptySet</a> is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a> and thus _not_ an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>. thing Thing <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> is the "universal collection": the collection which, by definition, contains everything there is. Every thing in the Cyc ontology -- every <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a> (of any kind), every <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a>, and every <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a> -- is an instance of (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViBBJwpEbGdrcN5Y29ycA" class="cyc_term">isa</a>) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. Similarly, every collection is a subcollection of (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViBDpwpEbGdrcN5Y29ycA" class="cyc_term">genls</a>) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. Trivially, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> is both an instance of and a subcollection of itself, and is not a subcollection of any other collection. (Note that the above reference to "every thing in the Cyc ontology" is not meant to be limited to things actually reified in the Cyc system, but includes (e.g.) every instance -- reified or not, known or not -- of every collection recognized by Cyc.) Pretty String (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwLSVCpwpEbGdrcN5Y29ycA" class="cyc_term">prettyString</a> TERM STRING) means that STRING is the English word or expression (sequence of words) commonly used to refer to TERM. The predicate <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwLSVCpwpEbGdrcN5Y29ycA" class="cyc_term">prettyString</a> is used by the code which generates CycL to English paraphrases, but its applicability is not restricted to this use. prettyString <code>(<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rZOAVeiYGEdqAAAACs2IMmw" class="cyc_term">broaderTerm</a> TERM1 TERM2)</code> means that <code>TERM2</code> is broader than <code>TERM1</code>, in an extremely general sense of "broader". For example, <code>TERM2</code> is, in the relevant sense, broader than <code>TERM1</code> if any of the following hold: <code>TERM2</code> is a collection that subsumes <code>TERM1</code>; <code>TERM2</code> is a collection that has <code>TERM1</code> as an instance; <code>TERM2</code> is a collection, instances of which have instances of the collection <code>TERM1</code> as parts; <code>TERM2</code> has <code>TERM1</code> as a part; This list of reasons for why <code>(<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rZOAVeiYGEdqAAAACs2IMmw" class="cyc_term">broaderTerm</a> TERM1 TERM2)</code> could hold is not exhaustive, but it should give a good indication of how general the <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rZOAVeiYGEdqAAAACs2IMmw" class="cyc_term">broaderTerm</a> relation actually is. BT broaderTerm An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> (q.v.). <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv7LKYpwpEbGdrcN5Y29ycA" class="cyc_term">Nothing</a> is in effect the collection-theoretical complement of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> (q.v.): the necessarily empty collection that is by definition equal to (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwTvAxJwpEbGdrcN5Y29ycA" class="cyc_term">rewriteOf</a>) (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwROrhZwpEbGdrcN5Y29ycA" class="cyc_term">CollectionDifferenceFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>). non-thing Nothing An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> (q.v.). <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv7LKYpwpEbGdrcN5Y29ycA" class="cyc_term">Nothing</a> is in effect the collection-theoretical complement of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> (q.v.): the necessarily empty collection that is by definition equal to (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwTvAxJwpEbGdrcN5Y29ycA" class="cyc_term">rewriteOf</a>) (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwROrhZwpEbGdrcN5Y29ycA" class="cyc_term">CollectionDifferenceFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>). non-thing Nothing AtemporalNecessarilyEssentialCollectionType A collection of collections. Each instance <code>COL</code> of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rqEYnNVMqEdaSKAACs0x8nw" class="cyc_term">AtemporalNecessarilyEssentialCollectionType</a> (ANECT) is a collection satisfying three conditions: (1) <code>COL</code> is disjoint with (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA45wpEbGdrcN5Y29ycA" class="cyc_term">disjointWith</a>) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAxJwpEbGdrcN5Y29ycA" class="cyc_term">TemporalThing</a>, (2) every instance <code>INST</code> of <code>COL</code> is an instance of <code>COL</code> essentially (i.e. <code>INST</code> is an instance of <code>COL</code>, and could not exist without being an instance of <code>COL</code>), and (3) condition (2) is a necessary truth about <code>COL</code>. Positive examples of ANECTs include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVieEpwpEbGdrcN5Y29ycA" class="cyc_term">Integer</a>, and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzZwpEbGdrcN5Y29ycA" class="cyc_term">Relation</a> (each of which is a collection of atemporals and is such that, necessarily, all of its instances are in it essentially). Negative examples include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjpUZwpEbGdrcN5Y29ycA" class="cyc_term">SpatialThing</a> (though arguably it is necessary that all of its instances are essentially instances of it, it is not disjoint with <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAxJwpEbGdrcN5Y29ycA" class="cyc_term">TemporalThing</a>) and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwP4FM5wpEbGdrcN5Y29ycA" class="cyc_term">UniqueAnatomicalPartType</a> (which, though disjoint with <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAxJwpEbGdrcN5Y29ycA" class="cyc_term">TemporalThing</a>, has instances, such as <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjvDpwpEbGdrcN5Y29ycA" class="cyc_term">Heart</a>, that could exist even if they weren't instances of it; e.g. it might have been the case that every creature with a heart had at least two hearts). There are no known examples of Cyc-reified collections satisfying conditions (1) and (2) but not (3), but one can be contrived. Suppose that all of today's winning lottery numbers were primes. Now consider the collection: (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvrhK-JwpEbGdrcN5Y29ycA" class="cyc_term">CollectionUnionFn</a> (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjkdpwpEbGdrcN5Y29ycA" class="cyc_term">TheSet</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjrdZwpEbGdrcN5Y29ycA" class="cyc_term">PrimeNumber</a> TodaysWinningLotteryNumbers)) This collection is clearly disjoint with <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAxJwpEbGdrcN5Y29ycA" class="cyc_term">TemporalThing</a> and, by hypothesis, all of its instances are in it essentially (as each prime number is essentially a prime number). But this last fact is not necessarily true of this collection: the collection might have had instances that belonged to it only contingently (i.e. not essentially), as it might have been the case that one of today's winning lottery numbers was non-prime, and no number is such that it is essentially one of today's winning lottery numbers. When asserting that something is an instance or specialization of a given instance of ANECT, it is appropriate to do so in the <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r3_SgQU2iEdaCwAACs0x8nw" class="cyc_term">UniversalVocabularyMt</a> (q.v.). Indeed, ANECT was specially defined to facilitate the movement of appropriate assertions to that microtheory. Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rGeylLJTfEdqAAAACs0uFOQ" class="cyc_term">PragmaticallyDecontextualizedCollection</a>. type of atemporal collection in which membership is necessarily essential NonAbducibleCollection The collection <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4roVp5xVzKEdiLrQAH6RYvVA" class="cyc_term">NonAbducibleCollection</a> is a sub-collection of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjl_ZwpEbGdrcN5Y29ycA" class="cyc_term">SetOrCollection</a>. Abductive inferences sometimes involve hypothesizing the existence of entities as part of the explanation of some assertion or set of assertions. Cyc will not hypothesize the existence of instances of the collections that are instances of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4roVp5xVzKEdiLrQAH6RYvVA" class="cyc_term">NonAbducibleCollection</a>. Roughly, abductive inferences consume conceptual / theoretical knowledge rather than produce it. So, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rHQdVmB_TEdaAAABQ2rksLw" class="cyc_term">SecondOrderCollection</a> is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4roVp5xVzKEdiLrQAH6RYvVA" class="cyc_term">NonAbducibleCollection</a> because Cyc should be employing existing theoretical knowledge about instances of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rHQdVmB_TEdaAAABQ2rksLw" class="cyc_term">SecondOrderCollection</a> rather than hypothesizing new instances. non abducible collection empty collection A collection of collections and a specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv1ZxY5wpEbGdrcN5Y29ycA" class="cyc_term">EmptySetOrCollection</a> (q.v.). A collection is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> if and only if it has no instances. Some collections are by their very nature necessarily empty; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv7LKYpwpEbGdrcN5Y29ycA" class="cyc_term">Nothing</a> (q.v.). Conversely, some collections are empty in some contexts and non-empty in others; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvhn_I5wpEbGdrcN5Y29ycA" class="cyc_term">Unicorn</a> might be empty in the context of the actual world but non-empty in certain mythological contexts. Similarly, a <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwIE23ZwpEbGdrcN5Y29ycA" class="cyc_term">TimeDependentCollection</a> might be empty at certain times and non-empty at certain other times; e.g. the collection of female US presidents is currently empty but will hopefully become non-empty some time in the near future. This last example demonstrates that <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> is itself a time-dependent collection. Note that each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> is <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA45wpEbGdrcN5Y29ycA" class="cyc_term">disjointWith</a> (q.v.) every collection -- including itself. Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a>. EmptyCollection An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a> (q.v.). <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv7LKYpwpEbGdrcN5Y29ycA" class="cyc_term">Nothing</a> is in effect the collection-theoretical complement of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> (q.v.): the necessarily empty collection that is by definition equal to (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwTvAxJwpEbGdrcN5Y29ycA" class="cyc_term">rewriteOf</a>) (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwROrhZwpEbGdrcN5Y29ycA" class="cyc_term">CollectionDifferenceFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>). non-thing Nothing