]> 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. non empty collection NonEmptyCollection A collection of collections and a specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rVwwqbE7rQdmaWqcELb2oPw" class="cyc_term">NonEmptySetOrCollection</a>. A collection is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> if and only if it has at least one instance. <p/> Some collections, aguably, are by their very nature necessarily non-empty; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a>. Conversely, some collections are non-empty in some contexts and empty in others; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwQBg3ZwpEbGdrcN5Y29ycA" class="cyc_term">Horse</a> is non-empty in the context of the present-day actual world but empty in certain counterfactual contexts in which horses never existed. 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/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> is itself a time-dependent collection. <p/> Note that each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rlyZyQm22EdaAAACgydogAg" class="cyc_term">intersectsWith</a> (q.v.) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. <p/> Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a>. Threatened-OrganismTypeByExistentialThreatLevel threatened organism type by existential threat level The collection of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjK65wpEbGdrcN5Y29ycA" class="cyc_term">BiologicalSpecies</a> and other <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjf5JwpEbGdrcN5Y29ycA" class="cyc_term">OrganismClassificationType</a>s that are threatened with extinction. This is less serious than being <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rXCwUsnS-EdaAAACgyZzFrg" class="cyc_term">Endangered_OrganismTypeByExistentialThreatLevel</a>. endangered species Endangered-OrganismTypeByExistentialThreatLevel The collection of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjK65wpEbGdrcN5Y29ycA" class="cyc_term">BiologicalSpecies</a> and other <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjf5JwpEbGdrcN5Y29ycA" class="cyc_term">OrganismClassificationType</a>s that are endangered (at risk of extinction). non endangered NonEndangered-OrganismTypeByExistentialThreatLevel The collection of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjK65wpEbGdrcN5Y29ycA" class="cyc_term">BiologicalSpecies</a> and other <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjf5JwpEbGdrcN5Y29ycA" class="cyc_term">OrganismClassificationType</a>s that are not endangered. HumanAdult A specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAkpwpEbGdrcN5Y29ycA" class="cyc_term">Person</a>, and an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvw00wJwpEbGdrcN5Y29ycA" class="cyc_term">HumanTypeByLifeStageType</a>. Each instance of this collection is a person old enough to participate as an independent, mature member of society. In most modern Western contexts it is assumed that anyone over 18 is an adult. However, in many cultures, adulthood occurs when one reaches puberty. Adulthood is <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVin4pwpEbGdrcN5Y29ycA" class="cyc_term">contiguousAfter</a> (q.v.) childhood. Notable specializations of this collection include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViyfpwpEbGdrcN5Y29ycA" class="cyc_term">AdultMaleHuman</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVix8ZwpEbGdrcN5Y29ycA" class="cyc_term">AdultFemaleHuman</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVibu5wpEbGdrcN5Y29ycA" class="cyc_term">MiddleAgedHuman</a> and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjZtZwpEbGdrcN5Y29ycA" class="cyc_term">OldHuman</a>. human adult A specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjl_ZwpEbGdrcN5Y29ycA" class="cyc_term">SetOrCollection</a> (q.v.); the collection of mathematical sets. An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a> can be any arbitrary set of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>s. A good way to explain this notion with respect to the Cyc ontology is to contrast <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a> with <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a> (q.v.). First, while the instances of a given collection all have some more-or-less significant (often &quot;natural&quot;) property or properties in common, the elements (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwGWaK5wpEbGdrcN5Y29ycA" class="cyc_term">elementOf</a>) in a given set might have nothing in common (besides membership in that set). Second, while it is in principle possible for two distinct collections to have exactly the same elements (with respect to a given context), this cannot happen in the case of sets, which are individuated strictly in terms of their extensions (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwN2YGZwpEbGdrcN5Y29ycA" class="cyc_term">extent</a>). Third (and specifically regarding their expression in the CycL language), unlike with collections, rarely will it be desirable to create a new constant to denote a particular set. Instead, a set will often be either (a) intensionally specified by a defining property via <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjX9pwpEbGdrcN5Y29ycA" class="cyc_term">TheSetOf</a> (q.v.), as in `(<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjX9pwpEbGdrcN5Y29ycA" class="cyc_term">TheSetOf</a> ?X (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA-ZwpEbGdrcN5Y29ycA" class="cyc_term">and</a> (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViBBJwpEbGdrcN5Y29ycA" class="cyc_term">isa</a> ?X <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVieEpwpEbGdrcN5Y29ycA" class="cyc_term">Integer</a>) (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAspwpEbGdrcN5Y29ycA" class="cyc_term">greaterThan</a> ?X 42)))', or (b) extensionally specified by enumerating its elements via <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjkdpwpEbGdrcN5Y29ycA" class="cyc_term">TheSet</a> (q.v.), as in `(<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjkdpwpEbGdrcN5Y29ycA" class="cyc_term">TheSet</a> 3 4 5)'; see also <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvcUeB5wpEbGdrcN5Y29ycA" class="cyc_term">ThePartition</a> and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwMTOWpwpEbGdrcN5Y29ycA" class="cyc_term">TheCovering</a>. Set-Mathematical set Cellular mobile telephone unit usually used in automobiles CellularTelephone cellular phone UnitedStatesPerson An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViWHZwpEbGdrcN5Y29ycA" class="cyc_term">PersonTypeByNationality</a>. Each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVj1zpwpEbGdrcN5Y29ycA" class="cyc_term">UnitedStatesPerson</a> is a person who is currently among that country's citizens (see the predicate <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViACJwpEbGdrcN5Y29ycA" class="cyc_term">citizens</a>), or is a participant in the <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r4VbZRgIxQdeJv7K4QRyNQg" class="cyc_term">NationalCulture</a> of the <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVikKpwpEbGdrcN5Y29ycA" class="cyc_term">UnitedStatesOfAmerica</a> (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvjD0_5wpEbGdrcN5Y29ycA" class="cyc_term">UnitedStatesCulture</a>). American frigate A collection. Warships which are larger than destroyers and smaller than cruisers. ModernFrigate type of thing Collection A specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjl_ZwpEbGdrcN5Y29ycA" class="cyc_term">SetOrCollection</a> (q.v.). This is the collection of all collections of things. Each <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a> is a kind or type of thing whose instances share a certain property, attribute, or feature. For example, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVkFc5wpEbGdrcN5Y29ycA" class="cyc_term">Cat</a> is the collection of all and only cats, and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwOckfJwpEbGdrcN5Y29ycA" class="cyc_term">BinaryFunction</a> is the collection of all and only functions taking two arguments. <p/> The notion of collection is fundamental to the Cyc ontology, and is thus difficult to define in a precise and substantive way. But it is instructive to compare it to the mathematical notion of a set (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a>). Like a set, a collection is an <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rpJ-nSEkJQdeC8NLkYPDBBw" class="cyc_term">AbstractThing</a> (i.e. aspatial and atemporal) that is not an <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a> (cf.), but instead has elements (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwGWaK5wpEbGdrcN5Y29ycA" class="cyc_term">elementOf</a>). Unlike a set, however, the elements or &quot;instances&quot; (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViBBJwpEbGdrcN5Y29ycA" class="cyc_term">isa</a>) of a given collection can vary from context to context, and it is possible for distinct collections to have exactly the same elements (i.e. to have the same <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwN2YGZwpEbGdrcN5Y29ycA" class="cyc_term">extent</a>) with respect to a given context. For example, the (non-reified) collections &quot;Chordate&quot; and &quot;Renate&quot; are co-extensional in the context of the present-day actual world, but have differring extents with respect to hypothetical contexts in which there exist creatures having hearts but not kidneys. This difference is sometimes summarized by saying that sets are &quot;extensional&quot; things and collections are &quot;intensional&quot; things. <p/> Many, though by no means all, of the collections reified in the Cyc ontology correspond to natural kinds or classes. It is particulary useful to reify collections that are difficult to define precisely, but about which there are many common-sense rules and other things to state. For example, it would not be worthwile to introduce a constant 'WhiteCat', both because it's easy to define the collection of white cats in terms of more general, already-reified notions (e.g. '(<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwEcGC5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionIntersection2Fn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVkFc5wpEbGdrcN5Y29ycA" class="cyc_term">Cat</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rBjWwGHS-EdaAAACgyZzFrg" class="cyc_term">WhiteColor</a>)'), and because there's not much to say about that particular collection. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rsX6vHnS6EdaAAACgyZzFrg" class="cyc_term">WhiteCollarWorker</a>, on the other hand, is a good collection to have reified, as it is hard to define precisely, yet is a collection about which there are many things to say. <p/> Some of the many reified specializations of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a> are <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rHIBS0h_TEdaAAABQ2rksLw" class="cyc_term">FirstOrderCollection</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwIE23ZwpEbGdrcN5Y29ycA" class="cyc_term">TimeDependentCollection</a>, and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVirnZwpEbGdrcN5Y29ycA" class="cyc_term">ObjectType</a>. Chimney The collection of chimneys, vertically-oriented portals that serve to direct hot or dangerous gases to an outdoor location, either by acting as a flue (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r6GZWLC-HEdqAAAACs71DGQ" class="cyc_term">Flue</a>) or (as with most modern home chimneys (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVj2g5wpEbGdrcN5Y29ycA" class="cyc_term">Chimney_HousePart</a>)) by serving as a rigid, protective (and often decorative) structure that contains the final part of the flue. chimney Individual <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a> is the collection of all individuals: things that are <i>not</i> sets or collections. Individuals might be concrete or abstract, and include (among other things) physical objects, events, numbers, relations, and groups. An instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a> might have parts or structure (including discontinuous parts); but <i>no</i> individual has elements or subsets (see <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwGWaK5wpEbGdrcN5Y29ycA" class="cyc_term">elementOf</a> and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvZA-05wpEbGdrcN5Y29ycA" class="cyc_term">subsetOf</a>). Thus, an individual that has parts (e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVj5FpwpEbGdrcN5Y29ycA" class="cyc_term">physicalParts</a> or <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVj-BJwpEbGdrcN5Y29ycA" class="cyc_term">groupMembers</a>) is <i>not</i> the same thing as either the set or the collection containing those same parts. For example, your car is an individual, but the collection of all the parts of your car is not an individual but an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>. This collection (unlike the car itself) is abstract: it doesn't have a location, mass, or a top speed; but it does have instances, subcollections, and supercollections. In partial contrast, the <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjmoJwpEbGdrcN5Y29ycA" class="cyc_term">Group</a> (q.v.) of parts of your car (while also not the same thing as the car itself) <i>is</i> an individual that has location and mass. Another example: A given company, the group consisting of all the company's employees, the collection of those employees, and the set of those employees are four distinct things, and only the first two are individuals. individual human A specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViV15wpEbGdrcN5Y29ycA" class="cyc_term">HomoGenus</a> and an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjK65wpEbGdrcN5Y29ycA" class="cyc_term">BiologicalSpecies</a>: this is the species to which modern humans belong, though strictly speaking (and not entirely uncontroversially amongst paleontologists) they comprise only a subset of it (namely &quot;homo sapiens sapiens&quot;). The species also contains Neanderthal and Cro-Magnon sub-species (both now extinct). Given the evidence of sophisticated tool-use, burial practices etc. even amongst the latter two sub-species, this collection is a specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAkpwpEbGdrcN5Y29ycA" class="cyc_term">Person</a>. See also <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rveQoDZwpEbGdrcN5Y29ycA" class="cyc_term">HumanBody</a>. HomoSapiens child HumanChild A specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwQtmz5wpEbGdrcN5Y29ycA" class="cyc_term">YoungHuman</a>, and an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvw00wJwpEbGdrcN5Y29ycA" class="cyc_term">HumanTypeByLifeStageType</a>. Each instance of this collection is a human in the childhood stage of life. Functionally, this life stage ends when the child begins to take responsibility for themselves, work, have children of their own (or, at latest, when the person's age greatly exceeds that at which most people reach those milestones). Generally, this means that it spans the period from birth to teenage years. Notable specializations of this collection include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVkMQJwpEbGdrcN5Y29ycA" class="cyc_term">MaleChild</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViBVZwpEbGdrcN5Y29ycA" class="cyc_term">FemaleChild</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjiv5wpEbGdrcN5Y29ycA" class="cyc_term">HumanToddler</a> and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjLpZwpEbGdrcN5Y29ycA" class="cyc_term">HumanInfant</a>. sailing frigate Frigate-SailingShip VariedOrderCollection A <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a> and the collection of all and only those <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>s some of whose instances (or instances of instances, or instances of instances of instances, etc.) are of different &quot;orders&quot;, where order is understood as follows. Let <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a>s be &quot;zeroth-order&quot; things, collections of (only) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjaApwpEbGdrcN5Y29ycA" class="cyc_term">Individual</a>s &quot;first-order&quot;, ..., and collections of (only) Nth-order things &quot;(N+1)th-order&quot;. A more precise, recursive definition, then, is: a collection COL is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rNs-F0CChEdaAAABQ2rksLw" class="cyc_term">VariedOrderCollection</a> if and only if COL has instances INST1 and INST2 such that either (i) INST1 and INST2 are of two different fixed orders N1 and N2, (ii) INST1 is of the fixed order N1 and INST2 is a varied-order collection, or (iii) INST1 and INST2 are both varied-order collections. <p/> For example, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rpJ-nSEkJQdeC8NLkYPDBBw" class="cyc_term">AbstractThing</a> is a varied-order collection since it contains both (zeroth-order) abstract individuals and (higher-order) collections. Other instances of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rNs-F0CChEdaAAABQ2rksLw" class="cyc_term">VariedOrderCollection</a> include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjjo5wpEbGdrcN5Y29ycA" class="cyc_term">Intangible</a>, <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/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a>, and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. Note that (by clauses ii and iii) any generalization of a varied-order collection is varied-order; and (by clause iii) any (non-empty) specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rNs-F0CChEdaAAABQ2rksLw" class="cyc_term">VariedOrderCollection</a> is varied-order. <p/> Note that <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rNooX_CChEdaAAABQ2rksLw" class="cyc_term">FixedOrderCollection</a> (q.v.) and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rNs-F0CChEdaAAABQ2rksLw" class="cyc_term">VariedOrderCollection</a> do _not_ constitute a partition of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>: since the notion of order described above is not applicable to sets, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a> (e.g.) and its specializations are neither fixed-order nor varied-order collections. variable-order Cyc collection A collection of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjl_ZwpEbGdrcN5Y29ycA" class="cyc_term">SetOrCollection</a>s. A set or collection is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rVwwqbE7rQdmaWqcELb2oPw" class="cyc_term">NonEmptySetOrCollection</a> if and only if it has at least one element. Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rv1ZxY5wpEbGdrcN5Y29ycA" class="cyc_term">EmptySetOrCollection</a>. non empty set or collection NonEmptySetOrCollection A collection of collections of collections. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a> is the collection of all (and only) types of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViAzJwpEbGdrcN5Y29ycA" class="cyc_term">Collection</a>s. More precisely, a thing COLLTYPE is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a> if and only if COLLTYPE is a non-empty collection all of whose instances are collections. Example: <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwPzQbJwpEbGdrcN5Y29ycA" class="cyc_term">PersonTypeByCulture</a>, each of whose instances is the collection of all persons who participate in some particular human culture, is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a>. Important specializations of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvtppU5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionType</a> include <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvWPoRpwpEbGdrcN5Y29ycA" class="cyc_term">DisjointCollectionType</a>, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA4pwpEbGdrcN5Y29ycA" class="cyc_term">SiblingDisjointCollectionType</a>, and <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rviPYH5wpEbGdrcN5Y29ycA" class="cyc_term">CollectionTypeType</a>. CollectionType type of collection non empty collection NonEmptyCollection A collection of collections and a specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rVwwqbE7rQdmaWqcELb2oPw" class="cyc_term">NonEmptySetOrCollection</a>. A collection is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> if and only if it has at least one instance. <p/> Some collections, aguably, are by their very nature necessarily non-empty; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a>. Conversely, some collections are non-empty in some contexts and empty in others; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwQBg3ZwpEbGdrcN5Y29ycA" class="cyc_term">Horse</a> is non-empty in the context of the present-day actual world but empty in certain counterfactual contexts in which horses never existed. 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/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> is itself a time-dependent collection. <p/> Note that each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rlyZyQm22EdaAAACgydogAg" class="cyc_term">intersectsWith</a> (q.v.) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. <p/> Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a>. A collection of collections. Each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwIE23ZwpEbGdrcN5Y29ycA" class="cyc_term">TimeDependentCollection</a> is a collection whose membership changes over time. For example, (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwPzX35wpEbGdrcN5Y29ycA" class="cyc_term">LiquidFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjAHZwpEbGdrcN5Y29ycA" class="cyc_term">Water</a>) is a time dependent collection. A given portion of water might be an instance of (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwPzX35wpEbGdrcN5Y29ycA" class="cyc_term">LiquidFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjAHZwpEbGdrcN5Y29ycA" class="cyc_term">Water</a>) in the summer, and an instance of the disjoint collection (<a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwPzX0JwpEbGdrcN5Y29ycA" class="cyc_term">SolidFn</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVjAHZwpEbGdrcN5Y29ycA" class="cyc_term">Water</a>) in the winter. In contrast, <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvVieEpwpEbGdrcN5Y29ycA" class="cyc_term">Integer</a> is a <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvzndCZwpEbGdrcN5Y29ycA" class="cyc_term">TimeIndependentCollection</a> (q.v.) because the collection of integers does not change its membership over time. time dependent collection TimeDependentCollection non empty collection NonEmptyCollection A collection of collections and a specialization of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rVwwqbE7rQdmaWqcELb2oPw" class="cyc_term">NonEmptySetOrCollection</a>. A collection is an instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> if and only if it has at least one instance. <p/> Some collections, aguably, are by their very nature necessarily non-empty; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvl2en5wpEbGdrcN5Y29ycA" class="cyc_term">Set_Mathematical</a>. Conversely, some collections are non-empty in some contexts and empty in others; e.g. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rwQBg3ZwpEbGdrcN5Y29ycA" class="cyc_term">Horse</a> is non-empty in the context of the present-day actual world but empty in certain counterfactual contexts in which horses never existed. 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/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> is itself a time-dependent collection. <p/> Note that each instance of <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4r_3mf2qedQdmNjeDW39lDKA" class="cyc_term">NonEmptyCollection</a> <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rlyZyQm22EdaAAACgydogAg" class="cyc_term">intersectsWith</a> (q.v.) <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rvViA9JwpEbGdrcN5Y29ycA" class="cyc_term">Thing</a>. <p/> Cf. <a href="http://sw.opencyc.org/2008/06/10/concept/Mx4rDKZQEKVnQdmACrINeAfsGw" class="cyc_term">EmptyCollection</a>.