Discussion of Dahlberg

Ingetraut Dahlberg is the founder of ISKO and the journal Knowledge Organization (formerly: International Classification). Her contributions within KO and concept theory include Dahlberg (1974, 1976, 1978a, 1978b, 1981, 1983a, 1983b, 1984, 1985, 1993, 1995, 2006).

Dahlberg bases the theory of KO on concepts. For example in the following quote:

"I would like to ad here that the most essential item in the theoretical background of knowledge organization is the fact that any organization of knowledge must be based on knowledge units - which are nothing else but concepts". (Dahlberg, 1993, p. 211).

I agree with what is said in this quote, although the term "units" should not be taken too literally. This expression should not, for example, be taken as an approval of the empiricist view of concepts, according to which simple sensations are associated with simple concepts, while complex concepts are based on association of simple concepts. However, if the term "unit" is understood in a way related to semantic holism, I agree with Dahlberg's statement, which bases the theory of KO on a theory of concepts.

It is important that the term concept theory is used in the subtitle of the journal: Knowledge Organization: International Journal. Devoted to Concept Theory, Classification, Indexing, and Knowledge Representation because this indicates the importance of concept theory to KO.

By and large, not much have been published in the journal Knowledge Organization about concept theory besides Dahlberg's contributions. Concept theory is a huge field in cognitive sciences, philosophy of mind, linguistics, sociology, and also in applied areas such as computer science (with Artificial Intelligence), terminology and translation. Concept theory in knowledge organization cannot just ignore such interdisciplinary contributions to concept theory. It is important that we relate to interdisciplinary findings and do not build our field on understandings that are unrelated to the general enquiry into concept theory.

One may ask, of course, whether research in KO have to relate to concept theory in philosophy and other fields? In my opinion, we have no choice. The tendency to base our fields of understandings of knowledge, language and science that are not related to general theories of knowledge, language and science is not proper scholarly or scientific quality. I find, for example, that Moss, 1964, is an important scholarly contribution in relating Ranganathan's categories to those of Aristotle. Ranganathan (and his many followers) have in my opinion mostly failed to live up to scholarly norms by assuming that Ranganathan's categories are original and by not examining the presumptions on which they are constructed and confronting those presumptions with other theories of language, knowledge, categories and so on. Miksa (1998, p. 75) writes in relation to Ranganathan's theory that it "is little more than unsupported speculation." That is indeed a serious criticism, but that is what is at stake if we do not base our theories and concepts on proper ground.

Dahlberg is a pioneer in KO and in basing it on concept theory. I find this important, and I also find it important that concept theory is mentioned in the subtitle of the journal Knowledge Organization. I also recognize that Dahlberg have made serious scholarly work by relating her view to broader views, including Aristotle and Gottlob Frege.

"Knowledge Organization is the science of structuring and systematically arranging of knowledge units (concepts) according to their inherent knowledge elements (characteristics) and the application of concepts and classes of concepts ordered by this way for the assignment of the worth knowing contents of referents (objects/subjects) of all kinds." (Dahlberg, 2006)

I agree that KO is basically the organization of concepts. However, the word "inherent" characteristics strikes me as problematic. Is the concept [democracy] determined by an analysis of some "inherent" characteristics, or is it determined by the meanings assigned to the word 'democracy' by different people? The meaning of the word 'democracy' is different in different theoretical and political views. It is known, for example, that the former state Eastern Germany was termed "Deutsche Demokratische Republik" (DDR). This may, of course, be dismissed as propaganda. However, a kernel of truth remains: That liberalist ideology tend to associate the word "democracy" with some formal rights, while socialist ideology tend to associate democracy with equal economic possibilities not determined by market forces but determined by public laws. To claim that there is one true, objective definition of "democracy" independent of theories and ideologies is a rationalist theory of concepts. (One candidate for such a rationalist definition of [democracy] is the definition provided by the Danish lawyer Alfred Ross: Democracy is a kind government in which an opposition is allowed and exists). The understanding of concepts that I find most useful, is the idea that a concept, say [democracy] are serving human interests and goals by the people using them, implying that different goals, values and theories define concepts differently. This is the core of a pragmatic theory of concepts. As an alternative to the analysis of "inherent" characteristics of concepts, I find it most important to analyze the underlying goals, values and consequences associated with the understanding of different meanings or concepts.

The reader should be prepared that there is no generally accepted definition or view of what concepts are, how they should be defined. Rey (1995, p. 192) summarizes the situation in this way:

"We might summarize the present situation with regard to candidates for “concepts” that have been discussed here as follows: there is the token representation in the mind or brain of an agent, types of which are shared by different agents. These representations could be words, images, definitions, or “prototypes” that play specific inferential roles in an agents cognitive system and stand in certain causal and covariant relations to phemomena in the world. By virtue of these facts, such representations become associated with an extension in this world, possibly an intension that determines an extension in all possible worlds, and possibly a property that all objects in all such extensions have in common. Which of these (italicized) entities one selects to be concepts depends on the explanatory work one wants concepts to perform. Unfortunately, there is as yet little agreement on precisely what that work might be”.

Smith, Ceusters & Temmerman (2005+ personal communication) argues that we should not talk about concepts at all, only about entities in reality. This view is not much different from Dahlberg (1978, p. 144), who states: "A proper categorization of concepts may rather follow a categorization of referents". This view is also related to my own realist understanding of concepts. I do think that we should speak of referents or entities in reality, but I also believe that different persons (or broader: different agents) classify objects differently and that the concept of concept is useful for talking about different conceptions. But we may conclude that the even the fruitfulness of the concept of concept is disputed in the literature.

If one go to a book termed Concepts: Core Readings (Margolis & Laurence, 1999) we expect of course to have the most important views and theories of concepts presented. However, this book contains no systematic presentation or discussion of the classical theories of Plato and Aristotle (only Plato's dialog Euthyphro without any comments or discussion). You have to go outside this book, for example, to Sutcliffe (1993) and Weitz (1988) to have a proper introduction of the classical theories of concepts by Plato and Aristotle. This is almost unforgivable because the two most frequently named theories in the literature on this subject are those made by Aristotle and Wittgenstein/Rosch. In other words: the editors of this "core readings" have not been qualified to identify "the core readings". The reader trying to get an overview of concept theory have to do a lot of searching and reading.

This impression is verified by what Weitz (1988) writes in the introduction to his own book on concepts:

"Because much evidence by way of historical analysis of traditional theories of language and meaning has accompanied and supported this contemporary critique of them, one would naturally suppose that similar evidence is available to vindicate the wholesale condemnation of traditional theories of concepts.

To my amazement and incredulity, I could find no book on the history of philosophical theories of concepts. There are, of course, Encyclopedia articles on CONCEPTS; however, these are, without exception, either too brief, too general or delinquent, contain too many inaccuracies and, on the whole, simply repeat the historical clichés of their predecessors. Dictionaries, too, are unhelpful, as are the more detailed Etymologies and Lexicons. What, then, of independently written essays or chapters of books on the different philosophers? Here, one finds a great deal on Kant's or Frege's theory of concepts, and much on Aquinas' or Leibniz'. But there is nothing, except paragraphs in chapters of books or in essays, on Plato's theory of concepts and, even more surprising, on Descartes', since he is preoccupied with what he refers to as `concepts' when he turns from Meditation to Reply, for example. And the little that there is on these two philosophers - that, for example, Plato's theory of concepts is that concepts are forms among the forms; or that Descartes means by a concept a variant of an idea - it soon became apparent to me is incorrect.

To one, like myself, who is not a specialist in the history of philosophy, this whole business of an individual philosopher's theory of concepts and of the history of theories of concepts, from Plato on, became confusing. The hope persisted that somewhere, someone - surely some German scholar, whose colleagues had devoted their lives to Plato's theory of justice or to the etymology of arête - had written a long, accurate history of philosophical theories of concepts.

That I could find no such survey dictated the writing of this book, entirely concerned with the history of philosophical theories of concepts. If I am right in claiming that such a survey does not exist, then this history of philosophical theories of concepts is the first. And in this regard, it will have realized one of its aims even if, disagreed with, in its parts or as a whole, it only provokes others to do the history better or differently.

But, it may be asked, is this history needed ? Obviously, it seems so to me, first, because any important idea and related set of doctrines about it that have a history enjoin and invite meticulous delineation of them. Second, no contemporary criticism of traditional theories of concepts nor, I think, any putatively original and true theory of concepts and the having of them can long ignore the competing theories of the past." (Weitz, 1988, xiii-xiv)

I believe the above is sufficient to conclude that the current understanding of concepts is rather messy. I believe the main raison is, that concepts is part of cognitive theories, which are themselves messy because mainstream research have sought the answer in the wrong place, in psychology rather than in epistemology. Concepts have been psychologized rather than epistemologized. (An I believe that Dahlberg shares this view).

I agree with Dahlberg (1978, 2006) that a concept may be regarded as a unit of knowledge (although statements or assertions may also be so regarded). The next step should thus be rather obvious: To have a look of different theories of knowledge (i.e., epistemologies) and learn how they understand concepts. My claim is that the major theories of knowledge have rather different conceptions of the word "concept", and that a fruitful understanding of [concept] is intimately linked to a fruitful theory of knowledge. Before I continue, it is important to say that I do not consider different epistemologies equally fruitful or true. I do not discuss different theories of knowledge because I believe that anyone can just choose a theory and work further from that basis. I am defending a particular view of knowledge inspired by, in particular, 'activity theory', American pragmatism and the theory of scientific paradigms suggested by Thomas Kuhn. Consequently, I am rejecting many other theories as problematic. My view may turn out to be problematic, but in demonstrating this, a better theory of knowledge have to be proposed. To develop a fruitful theory of knowledge is like provide other solutions such as developing good scientific explanations. The need to introduce other theories of knowledge is caused by the fact that they are underlying all discussions in the literature, why it is necessary to know about them in order to understand and follow the arguments put forward by all participants in the discussion and to verify, falsify or clarify any position.

In order to help students and colleagues overview the field of epistemology, I have established The epistemological Lifeboat (2005) with my colleague Jeppe Nicolaisen at http://www.db.dk/jni/lifeboat/home.htm . Different epistemological theories or positions are presented ( http://www.db.dk/jni/lifeboat/Positions.htm ). In order to simplify I shall in the following only discuss concept theory in relation to what I regard the basic epistemological positions: rationalism, empiricism, historicism (with hermeneutics) and pragmatism. These four positions have important, but clearly conflicting views of what concepts are, and thus also on how to organize them in KO. It is my claim that it is in the clarification of those four theories of knowledge that the key to a theory of concepts must be found.

Before considering classical rationalism shall the views of Plato and Aristotle briefly be introduced. Sutcliffe (1993, p.37) says. “[I]t appears that there was no direct ancient Greek equivalent for the word concept.” In Plato the Form or Idea is the true object of knowledge, the thing we grasp with our reason. Plato believed that the essence of something was not the shape of it or the matter of which it was constructed or any physical property. We are able to recognize an object because we know its essence through its Form. The Form to him was some ethereal thing that no one could see or touch but that existed nonetheless. The Form of a triangle is an idea not created by humans, but the triangle that we see is. If one think of, for example, the mathematical “phi” as something that has always existed and is just discovered by man, then one is close to a Platonic understanding of that concept.

As implied by the citation above Aristotle did not use an equivalent for the word concept. “Subjects and predicates were called terms, and a major concern of Aristotle was with their definition” (Sutcliffe, 1993, p.37). One may say, however, that “Aristotle has a theory of concepts according to which they are definitional entities―logoi that are closed in their necessary and sufficient properties which serve as the governing correct use of the concepts and terms that convey them.” (Weitz, 1988, p. 266).

What today is recognized as 'classical rationalism' or 'continental rationalism' is associated with philosophers such as Decartes, Spinoza and Leibniz of the seventeenth and eighteenth centuries. Descartes thought that knowledge is based on clear and distinct innate ideas -also known as "concepts". Judgments based not on ideas originating in sensory perceptions, but the ideas that are drawn from the mind itself are rather "clear" and "distinct" ideas. He divided our ideas into three categories: adventitious ideas, such as our idea of red, are gained through sense experience; fictitious ideas, such as our idea of a hippogriff, are manufactured by us from other ideas we possess; innate ideas, such as our idea of God, of extended matter and of a perfect triangle, are placed in our minds by God at creation.

“The most common defence of the innate-idea thesis, however, takes the form of admitting experience as a source of ideas but then arguing that some concepts could not have been gained directly or indirectly from experience; that these concepts are innate is then offered as the best explanation of their existence. That the concepts could not have been gained from experience is generally defended in one or both of two ways. First, the content of the concepts is beyond what we directly gain in experience as well as anything we could gain by performing the available mental operations on what experience provides. Second, our possession of the concepts is presupposed by our ability to employ the very empirical concepts that might be thought to provide a basis for them in experience.” (Markie, 1998).

Some rationalist principles of concepts

(from Hjørland, 1997)

Simple (non-defined) concepts are concepts which cannot be defined from other concepts in interesting ways.
Fundamental concepts are concepts which are indispensable to describe or explain a topic.
Simple and fundamental concepts enter into some necessary relations to each other. These relations reflects basic principles of reason.
The analysis of a arbitrary topic leads to a number of simple and fundamental concepts.
Every concept can be organized in an all-embracing structure of concepts.
The difference between simple and compound concepts is absolute. It is not just the case, that something is simple and something is compound when seen from a certain point of view (knowledge interest) or in a certain respect.
Empirical experience can be used to check ideas on general connections. However, it is never decisive for the insight in these.
You can never determine the content of a concept by the presentation of examples of that concept. On the contrary: every sensory recognition presupposes that the perceiving person already has certain concepts ("carries something in the luggage").
An analytical statement is a statement, whose truth-value is logically established. To a rationalist, there exist necessary statements, which are not analytical. However, to an empiricist there is no necessity in the world, everything that happens is contingent.
The predisposition to realize basic concepts that does not originate from experience must be inborn. It is our way to form concepts, which determines the essential connections between the things, we can learn

'Classical empiricism' or 'the British Empiricists' are philosophers like Locke, Berkeley and Hume from the same period as continental rationalism. They criticized the Aristotelian doctrine of concepts as abstracted essential characteristics of things.

“The objection was the claim that we somehow have access to entities that lie outside the realm of ordinary experience. Forms or essences were thus subjected to skeptical attack, along with the doctrines of abstraction and innatism [innatism used by Plato and Descartes, not by Aristotle]. The empiricists had therefore to develop an alternative account of what is involved in the capacity to use words. Specifically, they argued that what is before the mind is a sensory image of the things thought about. By virtue of relations of resemblance among things and among sorts of things, we come to be able to use words to refer to things that are not present and to re-identify things or sorts of things when they are re-presented. The connections between the relations of resemblance and the words are established through acquired or learned conventions.” (Wilson, 1997; emphasis in original; internal references omitted).

Some empiricist principles of concepts

(from Hjørland, 1997)

All knowledge, which is not pure logical knowledge, originates from experiences (from the senses).
Knowledge of particularities and of contingent relations are only given a posteriori.
All knowledge based on experience concerns something particular (isolated); empirical knowledge is therefore fragmented.
The sensations of the individual human being are the basis for obtaining knowledge. (Individualism; methodological individualism).
Concepts, which are employed to describe and explain factual circumstances, come from sensory experiences.
Sensory experiences are private. Knowledge must therefore be subjective. (Subjective idealism).
Complex concepts must be defined from simple concepts, which refer to sense-impressions. (Associationism).

The difference between the rationalist and the empiricist understanding of concepts is related to the basic ways of obtaining knowledge. For the rationalists were kinds of logic thinking and deductions important, for the empiricists were sense impressions important. Consequently prefer rationalists to define concepts by logical means, i.e. by analyzing complex concepts into simple concepts whereas empiricists prefer to define concepts by observable and measurable characteristics. Rationalist methods tend to bring clearness and structure while empiricist methods tend to bring a lot of details. Rationalist methods may be criticized for being "speculative" while empiricist methods may be criticized for being collecting trivia because sensory observations presupposes that the researcher "carries something in the luggage". Applied to knowledge organization we may say that rationalist classifications tend to provide clear definitions and structures, while empiricist classifications have a better empirical foundation but tend to drown in trivial data. Obviously both views have something to offer and the strength of the one seems to be the weakness of the other.

Some historicist principles of concepts

(from Hjørland, 1997)

Knowledge is historically, socially and culturally determined.
The criteria of true knowledge are determined by historical and social conditions.
Concepts are not primarily defined from individual sensations or by eternal criteria, but from cultural learning and influence.
The function of knowledge is not only studied individualistically by focusing on the isolated and abstract human being, his or her ability to sense, remember, and form concepts, but in addition by involving the whole person's developmental history, both individually and collectively. Attention should also be given to the study of what knowledge actual performs and has earlier performed: The history of culture and ideas.
All experiences, even the most simple, happen only on the basis of an understanding of the coherence in which the phenomena form a part.
Simple and complex concepts are simple or complex in given contexts, not necessarily also in other contexts: The complexity of concepts is a relative phenomenon.
The mastering of a common concept implies the ability to use that concept on a multitude of phenomena in many different connections.
All experience happens from a certain perspective and in a certain historical and social context.
Experience is self-correcting (adjusting) based upon knowledge about its own history.
Knowledge is best studied by give an historical account for how relevant concepts, theories and interpretations has been developed in connection with the circumstances under which they have been developed.
Development of knowledge is connected with recognition (epistemical authority).
The individualistic account for the cognitive system provided by both empiricism and rationalism is seen as narrow-mindedness because they do not include the signification of the role of tradition and social communities for learning and conceptual development.

William James found that conceptions are subjective criteria for classifying objects in the world and concepts are the things so classified. In order to be able to react to the world, to think about the world and to represent the world in discourses human beings (as well as non-human subjects) have to have relatively stable relations to parts of the world. We have to be able to recognize something as being the Same. (James, 1890/1950, p. 459).

“The function by which we thus identify a numerically distinct and permanent subject of discourse is called CONCEPTION; and the thoughts which are its vehicles are called concepts. But the word “concept” is often used as if it stood for the object of discourse itself; and this looseness feeds such evasiveness in discussion that I shall avoid the use of the expression concept altogether, and speak of “conceiving state of mind” or something similar, instead. The word “conception” is unambiguous. It properly denotes neither the mental state nor what the mental state signifies, but the relation between the two, namely, the function of the mental state in signifying just that particular thing. . . . Each act of conception results from out attention singling out some one part of the mass of matter for thought which the world presents, and holding fast to it, without confusion [note omitted]. Confusion occurs when we do not know whether a certain object proposed to us is the same with one of our meanings or not; so that the conceptual function requires, to be complete, that the thought should not only say “I mean this”, but also say “I don’t mean that” [note omitted]. Each conception thus eternally remains what it is, and never can becomes another. The mind may change its states, and its meanings, at different times; may drop one conception and take up another, but the dropped conception can in no intelligible sense be said to change into its successor” (James, 1890/1950, p. 461-462).

Concepts and conceptions are thus subjective maintenances and classifications of parts of the world. Concepts allow us to concentrate on objects, they permit us to act in a world which is fluid or flowing out. They are always determined by some subjective interest, “and how the conception with which we handle a bit of sensible experience is really nothing but a teleological instrument. The whole function of conceiving, of fixing, and holding fast to meanings, has no significance apart from the fact that the conceiver is a creature with partial purposes and private ends. “(James, 1890/1950, p. 482).

Studies of how a term has been used cannot help us to decide how we should define it. When we use language and terms, we perform some kind of act, with the intention of accomplishing something. The different meanings of the terms we use are more or less efficient tools to help us accomplish what we want to accomplish. In this way, according to pragmatic philosophers such as Charles Sanders Peirce (1905), the meaning of a term is determined by not just the past, but also the future.

Toulmin's (1972/1977) understanding of concepts is explicitly Darwinian in that concepts, like species, are viewed as neither historically stable nor discontinuous. He argues that concepts evolve over time and that it is the prevailing conditions of their use in a scientific or other community that provides the motive, direction and rate of that change. Toulmin makes a differentiating between the content-knowledge of a science and the institutional aspects of science, such as the professional forums. He suggests that science is generally continuous because either the content or the institution will remain stable while the other changes. In response then the first will adapt, in an iterative process of constant change and constant stability. There is continuity because each generation is always taught by the preceding generation of scientists and also because the research questions a community is interested in are predicated on the current concepts they hold, even when the results of those researches might indicate changes are needed to better adapt the concepts in response to other concepts or other facts about nature. As with the evolution of species, where most species adapt but some become extinct, a concept might be abandoned completely, but more often some aspect of the earlier concept remains.

A concept, e.g. [mass] includes both the word (linguistic symbol) ("mass") and the letter “m” (mathematic symbol), the ability to be used in both relativistic and non-relativistic equations, and some set of procedures for determining mass, though again these skills can and do change.

The pragmatic view of concepts may be understood as follows: To be in order to pursue goals and to plan future actions must intelligent systems – humans or machines – be able to classify some objects, behaviors or events as equivalent for achieving given goals. Concepts are ways of classifying the world. Any concept/classification may be more or less suited or unsuited helping the system achieving a particular goal. If a human culture, for example, do not conceptualize animals as eatable, that culture have fewer objective possibilities to feet its members compared to other cultures. An intelligent system must be able to form classes of objects that are equivalent in relation to a certain task. A common goal or a common use is the principle that unites the classes and that forms the concepts. This view of concepts is basically the pragmatic view. It is explicitly shared by some researchers in cognitive science and artificial intelligence (AI), such as Michalski (1992, p. 249), but people associated with machine learning and AI have, however, to simplify the nature of concepts, why they in reality may operationalize concepts differently.

Andersen et al. (1996, pp. 348-51) provide an account of two theories of concepts, namely the “classical” theory (dating back to Aristotle)[3], where concepts are defined by a set of individually necessary and jointly sufficient properties, and Kuhn’s (1996, 1970, 1996, p. 349) theory of concepts informed by the so-called “prototype theory” associated with Ludwig Wittgenstein and Eleanore Rosch, where objects in a similarity class “. . . need bear no more than a family resemblance to their fellows, and hence that the concepts corresponding to these similarity classes are family resemblance concepts”[4]. Kuhn, in rejecting a specific set of properties as the basis for class membership, thus rejects the traditional view that concepts and classes can be defined in terms of necessary and sufficient properties.

Andersen (2002, p. 99) points out that “. . . family resemblance concepts form hierarchical structures in which a general concept decomposes into more specific concepts that may again decompose into yet more specific concepts, and so forth – in other words taxonomies”. Hereby, Andersen suggests that classification may be explained systematically from a family resemblance point of view and furthermore (p.
99) argues that the family resemblance account allows for taxonomies being dynamic entities, which may undergo change.

According to Andersen (2002, p. 102) theories or models “. . . provide the causal and explanatory links that hold individual concepts together and establish taxonomic relations to other concepts”. This account differs markedly from the “classical” theory of concepts, where concepts are defined by a set of individually necessary and jointly sufficient properties. Here, that which holds concepts together and that which establishes relations to other concepts are theory-independent.

Some pragmatist principles of concepts

Concepts are subjective ways to classify things in the world. Although they are subjective, they are mostly shared by a group of people: They are not just individual.
Concepts are related to conceptions, ways of understanding.
Concepts are more or less fruitful ways of classifying things in the world in relation to given goals, interests and values. Different concepts are needed for different goals. In other words:
Concepts are political, they serve some interests at the expense of other interests.
Given concepts are related to standardized practices in communities. People wanting to change standardized practices need to challenge existing concepts.
Concepts are not arbitrary associations between properties of things and words: Concepts have "historical depth". When you learn a concept in a culture, you learn something about humankinds collective experience. For example, when you learn the concept [cup] you do not just learn about some physical properties, you also learn about the affordances of some objects.
Concepts cannot be determined just be examining their history. Concepts have to be examined by confronting them with what kind of future tasks they are going to support. The concept [document] may for example, play a different role in the digital culture, why it may need to be reconsidered.
People may learn to use concepts without realizing their underlying values and consequences. Normally people use concepts without analyzing their implications. Studies of different conceptions and ways of understanding and clarifying of the goals, values and interests the concepts are going to serve are important. In other words: critical reflections and studies.
Scientific concepts may often seem 'objective' because no competing conceptualization can provide satisfactory explanations and because there exist a high level of consensus about the underlying goals, interests and values.
A closer analysis of any given domain tend to uncover different views or 'paradigms' representing different interests and tending to develop different concepts.
In a given literature there will usually exist a mixture of different conceptions more or less clearly related to, for example, empiricist, rationalist, historical or pragmatic ways of understanding. Any literature tends to be a merging of different conceptions and ways of understanding each representing different values, goals and interests. The uncovering and explication of such conceptualizations is a relevant task for knowledge organization.

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