1 Concepts, Conceptual Systems, Definitions. PA116 – L11 (c) Zdenko Staníček, Sept 2010, Nov 2012 OPVK_MU_EN_stred_2.jpg 2 Topics •Motivation •Concepts •Higher order objects •Definition – what actually is it? •Linguistic definition •Conceptual systems •What means DUM 3 Motivation •What is “concept”? •problems of communications among various professional cultures •chaos in the concept of “concept” •concept is a class ... (most computer scientists) •concept is a set of properties ... •concept is an independently identifiable structured construct composed of knowledge primitives and/or other concepts ... (H. Kangassalo, The Finish School) 4 Corrected Triangle of Denotation correction of Frege-Church's “expression denotes the reference” and “expression expresses the sense” natural language expression object construction denotes expresses constructs 5 Basic (commonly shared) intuition (Platon, Bolzano, Frege, Church, …) •Concepts are “identification procedures” allowing common shared understanding of what we actually talk about •Concepts are mental procedures our mind has to execute to identify an object which is focused on 6 Jeff Hawkins’ Hypotheses (in his book: “On Intelligence” ) •Neocortex stores sequences of patterns •Neocortex stores patterns in an invariant form (invariant representation) •A sequence of pattern is a pattern again •Neocortex stores patterns in a Hierarchy •Neocortex doesn’t distinguish between external inputs and internal inputs •Thus: Concepts are invariant representations of sequences of (elementary) patterns. touch audition vision 8 Example of “concepts”/ expressions pairs •(1) Prime number (2) Natural number which has exactly two divisors •(1) equilateral triangle (2) equiangular triangle •(1) sons of the heir to the throne (2) men whose father is the heir to the throne •(1) and (2) identify the same object anyway •(1) and (2) are always different identification procedures (we have to invest intellectual endeavour to recognize that the given expressions identify the same object) > 9 Are there Objects in constructions? •Let’s have x(sin x), x real number, sin: R  R x(Salary x), x::EMPL, Salary: EMPL  R •is sin, or Salary, object or construction? •according to the definition they are subconstructions •sin, Salary ... are atomic constructions •It is necessary to separate precisely the world of objects from the world of their constructions, as we have no objects in our Memory – therefore we need trivialisation: •Let X be any object (or construction), then trivialisation 0X constructs just X without any change. •it is about elaboration and expansion of the definition of atomic construction •Trivialisation constructs objects simply by pointing them. 10 Self-reference “on the stage” •TIL with simple theory of types: –constructions are out of the focus of our research –constructions are only tools for a research of the World-of-objects •What if we focus on a construction as an object of interest? •Remember: Neocortex doesn’t distinguish between external inputs and internal inputs 11 selfreference Self-reference 12 OBJECT “which is focused on” closed CONSTRUCTION linguistic EXPRESSION no object (strictly empty)‏ Extension/Intension closed CONSTRUCTION reference in the real word at a specific time represents denotes identifies Self-reference in a scheme 13 OBJECT “which is focused on” closed CONSTRUCTION linguistic EXPRESSION no object (strictly empty)‏ Extension/Intension closed CONSTRUCTION reference in the real word at a specific time represents denotes identifies Self-reference in a scheme CYBERSPACE PHYSICAL WORLD 14 Consequences •Bertrand Russell: Ramified Theory of Types •Pavel Tichý: “… consistent logic theory is not possible to build on simple theory of types …” •Constructions need to be included into observed objects of interest … •… and what about constructions of constructions …? 15 Constructions: an overview and extensions (1) •Trivial construction – trivialisation 0X object X is identified by itself (is constructed by pointing on it); external input pattern to our neocortex (or to Memory) •Atomic construction – variable it constructs an object of a given type depending on a total function from variables to objects (called valuation) •Execution construction 1X Using X as construction, execution constructs what X constructs. If X is not a construction, using X does not construct anything – we say that the construction is v-improper for any valuation v. 16 Constructions – overview (2) •Double-execution construction 2X Using result of the execution of X as construction, the double-execution constructs what result of the execution of X constructs. If X is not a construction or X does not construct construction, double-execution of X does not construct anything – we say that the construction is v-improper for any valuation v. Constructions – overview (3) •N-tuple or sequence construction (X1, …, Xn) … see DM1 or referred study materials •Projection construction X(i) … see DM1 or referred study materials • 17 18 Constructions – overview (4) •Abstraction construction – closure λx1…xn(X) … see DM1 or referred study materials •Application construction – composition [XX1 …Xn] … see DM1 or referred study materials • • •This is a complete apparatus of constructions which allows to describe also a self-reference (and what happens in the Fundamental Hierarchy) •Construction is unable to be mentioned as object of interest in Simple Theory of Types; Ramified Theory of Types is needed ! 20 Definition of types above EB •Ramified theory of types is built above used cognitive base, i.e. above EB introduced in Simple Theory of Types. Following definition contains double nested inductive sub-definition. •T1 (induction precondition): every simple type above EB is type of order 1 •Cn (constructions of order n): describes constructions of order n; they constructs objects of order n •Tn+1 (inductive step – types of order n+1): inductively describes what types of order n+1 are 21 Cn (constructions of order n): •Let  be a type of order n. Then 1.every variable which v-constructs -objects is a construction of order n 2.if X is -object, then 0X is a construction of order n 3.Let X1, …, Xn be constructions of order n. Then (X1, …, Xn) is construction of order n. 4.Let X be construction of order n which constructs objects of the type (T1, …, Tn). Then for all i = 1, …, n, X(i) is a construction of order n. 5.Let x1, …, xn, X be constructions of order n, let xi be variables. Then λx1…xn(X) is construction of order n. 6.Let X, X1, …, Xn be constructions of order n. Then [XX1…Xn] is construction of order n 22 Tn+1 (types of order n+1): •Let Consn be a class of all constructions of order n. •Consn and every type of order n is a type of order n+1. •Let 1, …, m be types of order n+1. Then Cartesian product 1 … m, denoted (1, …, m), is a type of order n+1. •Let , 1,…, m be types of order n+1. Then ((1,…, m) → ), i.e. a class of all partial functions from 1…m to , is a type of order n+1. •Nothing but what is constructed according to steps 1 through 3 is a type of order n+1. •(see definition of type within Simple Theory of Types in the study materials) 23 Higher order objects •If  is a type of order n, then every X   is an object of order n. •Objects of order n, where n  1, are called higher order objects. •The class of all constructions of objects of order n composes a type of order n+1. •Every construction of order n is an object of order n+1. 24 … And for what is it useful? •Higher order objects and their constructions, especially trivialisation, provide the inspiration for MENTION and USE of connections, categories, operations and rules which are fundamental constructs for modeling. •Knowledge is principally recursive ! •To understand (or to model, to execute) a knowledge-intensive Service System 25 Higher order objects •Order of an object depends on what the object constructs. •Constructions of order 1 construct objects of types of order 1, so they belong to types of order 2 and they are objects of order 2. •Constructions of order 2 construct objects of types of order 2, so they belong to types of order 3 and they are objects of order 3. •etc. •No construction can be found among objects of order 1. •Simple Theory of Types deals only with objects of order 1 and works with type hierarchy which is infinite but still in limits of order 1. •Ramified Theory of Types includes constructions as objects, thus it adds a new (infinite) hierarchy of orders. •Only a modern physics knows what elementary objects of the physical world are in itself. We have in our brains only constructions !!! What is interesting is: under influence of the same environment and situation these constructions are almost certainly the same !!! 26 Concepts – an approximation •Based on the use of Ramified Theory of Types: •Concepts are closed constructions > 27 Rules of -calculus •constructions x[0sin x] and y[0sin y] are considered to be (quasi)identical ( - rule) •constructions [(x(0sin x)) 0] and 0sin 0 dtto (rule) •constructions 0Prime and x[0Prime x] dtto ( - rule) •constructions 02 and x[0= x02] dtto ( - rule) 28 Why this (quasi)identity ? •When any two (quasi)identical closed constructions are USE-d as Constructions they give the same result or they both are improper. •There is no reason to distinguish between two (quasi)identical close constructions when they are MENTION-ed as Objects. 29 Quasi-identity •Closed constructions c1 and c2 are quasi-identical if they are alpha- or beta- or gamma- equivalent. We say that c1 and c2 are in relation Quid. •If ( c1 Quid c2 ), then c1 constructs the same object as c2 , or both c1 and c2 are improper. • •Lemma: Quid is an equivalence relation. •>>Prove it! 30 Concepts •Concept is a closed construction belonging to a class of quasi-identical closed constructions. As constructions from a given class are not distinguished in the USE mode, we will not distinguish them in the MENTION mode. • •In Aleš Horák's dissertation, there is more precise definition based on canonical forms of constructions and sequences of quasi-identical constructions which are gradually derived from these forms. However, our definition is sufficient for our purpose. 31 OBJECT “which is focused on” CONCEPT (closed construction)‏ linguistic EXPRESSION Strictly empty Extension/Intension Concept (closed construction)‏ higher order object reference in the real word at a specific time represents denotes identifies Essence of communication, understanding, and modeling 32 CYBERSPACE PHYSICAL WORLD OBJECT “which is focused on” CONCEPT (closed construction)‏ linguistic EXPRESSION Strictly empty Extension/Intension Concept (closed construction)‏ higher order object reference in the real word at a specific time represents denotes identifies Essence of communication, understanding, and modeling 33 Role of objects and constructions in conceptual (data) modeling •OBJECTS – what is focused on •CONSTRUCTIONS – what identifies focused objects (for all participants in a communication so that they have the same objects in the mind during this common communication) •Conceptual (Data) Model contains constructions of objects (constructions which identify objects) corresponding especially to non-trivial intensions •Database contains linguistic EXPRESSIONS (of a special language) which denote some objects (corresponding to extensions) that was sufficient until recently while (primary) information systems were constructed only > 34 Service Systems—Modeling and Execution (SSME*) •Service System is a flexible and adaptable composite of people, technology, other service systems, wrapped together with specific knowledge and information, which can be seen at least in one context as a game of Client, Provider and Target, for the benefit of the Client. •To model or to execute a Service System properly, higher-order-objects are unavoidable !!! CLIENT PROVIDER TARGET Individual or Organization or Technology (owned or operated by Provider) Individual or Organization (private or public, human or semi-human living or artificial) The reality to be transformed or operated on by P for the sake of C (people and dimensions of, business and dimensions of, products, technical artifacts, environment, information, codified knowledge) P provides service to C; C co-operates with P; value co-production; value proposition; information shared P is responsible for actions with T C is owner of T or C needs an added value on T C P T MENTION C P T C P T TIME 37 What a definition is What is defined, and by what it is defined 38 What is defined here? •“Employee of an organization is a human which has a contract of employment with the organization.” •… it is obviously not a definition of the expression “employee” !!! •define = delimit, demarcate, set aside, identify •does it identify a concept EMPLOYEE ??? (= closed construction of a class of Quid constructions where each of them constructs an intension (property) “to be an employee”, i.e. constructs an object) > 39 So what is defined? •“Employee of an organization is a human which has a contract of employment with the organization.” •! It identifies an object with a specific property. •Conclusion: Objects are defined and they are defined by concepts. > 40 Examples of definitions •Entity sort #EMPLOYEE Object of the type #Employee is every person which has concluded a contract of employment with an organization according to the Labour Code of the Czech Republic. •Entity sort #ARTICLE Object of the type #Article is every product or service or right which can be a subject of a sale including products, services and rights that did not exist yet but can be made for business activities. 41 Is it all? And, what about: •A number having exactly two divisors we will call prime number. –Is this a Definition? Isn’t it an Abbreviation? •What is a “Conceptual System”? –Is it just a simple collection of concepts? –Or, is it something more … ? •What is the role of Language (natural or artificial one) in this game with Concepts, and in wrapping them into Conceptual Systems ? Conceptual systems and conceptual models A deeper insight into Cyberspace (what happens in the brain-engine when the inner inputs 10-times exceed the external ones…) What can help us to understand Service Systems and their agents communication and thinking Conceptual systems and conceptual models •Primitive/Derived Concepts •Relativity of primitive/derived with respect to a chosen conceptual system (domain) •Language of conceptual system (domain) •Linguistic definition •Hierarchy of languages over a conceptual system •The nature of natural language •What is a conceptual modeling in fact? Simple Concepts •A simple concept is a trivial construction of an object (which is not a construction) or of an variable •Where to find it within the Fundamental hierarchy? Simple Concepts •A simple concept is a trivial construction of an object which is not a construction or of an variable •Where to find it within the Fundamental hierarchy? •A simple concept is a construction 0X, where X is a variable of any type a of the ramified hierarchy or an a -object which is not a construction. •Simple concepts point objects and this is clear without any additional explication. Not simple concepts point objects, too, but additional explication is needed to understand what the matter is. •The extension of a concept C is the object constructed by C. •The content of a concept C is the set of all simple concepts that are subconstructions of C. Concept's extension and content Conceptual system C1, …, Cm simple concepts C1, …,Cm --- simple concepts (primitive concepts) Cm+1, Cm+2, … derived concepts Conceptual system CS •C1, …,Cm --- simple concepts •Cm+1, Cm+2, ... be concepts, all of them distinct from any of C1, ..., Cm, such that the subconstructions of Cm+i, i > 0, are only –members of the set C1, …, Cm, and –variables ranging over those types that are composed of types given by C1, ..., Cm. •PCS = {C1, …,Cm} primitive concepts •DCS = {Cm+1, Cm+2, ... } derived concepts •CS = PCS È DCS Relativity of primitive/derived DOMAIN 1 p primitive concepts DOMAIN 2 primitive concepts If we see in a way a similarity, we use the same, already known, words. The nouns are variables “of type a” from the ramified hierarchy. What is primitive within one domain can be derived in other domain. What is primitive for an expert can be derived for a beginner. How we evaluate the situation depends on a Context. The semantics is given by the couple: (Domain, Conceptual System). Concepts and Context relationship •There is always lot of contexts from which a domain in a situation could be evaluated and/or studied. •There is no one context which could be called “a master context” ! •Hence, there is no one conceptual system which could be said “a master one”. •Cn(…) : Concepts are context independent; selection of Conceptual System is context dependent ! What is an impact on Service Systems •To work in a domain (to provide services), namely to provide innovations of services in a domain means to develop the conceptual system of this domain. •Remember the three categories of information and knowledge which must be shared by agents of a Service System: –Language*) –Laws (or Rules) –Measures Linguistic definition •The standard explication of what a definition is speaks about “definiendum” (i.e., what is defined) and “definiens” (i.e., by which it is defined). •The standard approach is a linguistic one, as it is based on NL (natural language) expressions and natural language semantics. •These standard definitions have the form •'Definiendum = Definiens'. •This is a short-cut! It introduces a name for something. examples •We will call Prime Number each natural number having exactly two divisors. •By the term Employee we will mean each person having valid employment contract with a company or an institution. •On the contrary: •An object of a sort (#Emp) is each such person that has a valid employment contract with a company or an institution. •… this sentence describes a construction of an object (entity sort) using given properties. At the same time it introduces a name of the entity sort. •This is a combination of a pure definition in the basic sense and of a linguistic definition. *) Language and CS •Let CS be a conceptual system based on PCS = {C1, …,Cm} •A language LCS of conceptual system CS is a language satisfying the following conditions: –There are simple expressions in LCS that represent C1, …,Cm. –If E is expression of LCS that represents construction X of a -objects, then there are grammatical rules of LCS that make it possible to create expressions Econs of LCS that represent any construction of any one of the 8 construction modes. –No other expressions are in LCS. This is not enough for a convenient communication and thinking ! We need a more comfortable tool ! Hierarchy of languages with respect to a conceptual system (1) •Let SEji denotes a simple language expression, i.e. not structured expression (not composed of other language expressions). •It is usual to take such expression as a name of this item which is denoted by this simple expression. •Let CEji denotes a complex language expression, a structured expression composed of other language expressions. Hierarchy of languages with respect to a conceptual system (2) •Linguistic definitions in a language of i-th level with respect to a conceptual system CS are introduced inductively: –Let L0CS be LCS. –Let LiCS, i > 0, results from Li-1CS by adding a set of simple expressions SEi1, ..., SEik, k > 0, together with expressions interpreted as true sentences: SEi1 = CEi1 … SEik = CEik where CEi1, …, CEik are complex expressions that contain only expressions occurring in Li-1CS. –The expressions SEij = CEij, i > 0, j = 1..k, are called linguistic definitions expressed by the language LiCS. Hierarchy of languages with respect to a conceptual system (3) •Simple expressions SEi1, ..., SEik, are definienda, complex expressions CEi1, …, CEik are definiens expressed by the language LiCS. Conceptual system and its hierarchy of languages C1, …, Cm simple concepts C1, …,Cm --- simple concepts (primitive concepts) L0CSi Cm+1, Cm+2, … derived concepts Hierarchy of Languages LjCSi Hierarchy of languages with respect to a conceptual system •NL contains a wide set of languages LjCSi of various conceptual systems CSi. •The hierarchy grows up to higher levels during the time in accordance with the step-by-step growing cognition of any given domain. •NL is not something completed with fixed meanings of particular expressions. •NL is a pool of particular hierarchies of languages over conceptual systems defining particular domains. •NL is a dynamic phenomenon which develops continually. • What is a conceptual modeling in fact ? (the last question!) What a conceptual modeling is in fact •Discovering of suitable concepts identifying objects in the Domain under Discussion (DuD). •Creating pragmatically a proper conceptual system. •Step-by-step designing of a hierarchy of languages with respect to the conceptual system. •Real understanding to DuD through previous steps, i.e. by creating of semantics of words connected to the domain. Semantics of NL expressions is not something which exist as a static phenomenon; Semantics is a mapping: (NL expressions, Domain) ® Concepts Semantics is created within the domain cognition process ! Conclusion • Thus the Conceptual Modeling is the way to understand –domains –environment –systems –exactly! –And, moreover, it is possible! … and aiming to create viable Service Systems it is necessary …