Argument map

A written text can be transformed into an argument map by following a sequence of steps. Monroe Beardsley's 1950 book Practical Logic recommended the following procedure:[12]

1. Separate statements by brackets and number them.
2. Put circles around the logical indicators.
3. Supply, in parentheses, any logical indicators that are left out.
4. Set out the statements in a diagram in which arrows show the relationships between statements.

A diagram of the example from Beardsley's Practical Logic

Beardsley gave the first example of a text being analysed in this way:

Though ① [people who talk about the "social significance" of the arts don’t like to admit it], ② [music and painting are bound to suffer when they are turned into mere vehicles for propaganda]. For ③ [propaganda appeals to the crudest and most vulgar feelings]: (for) ④ [look at the academic monstrosities produced by the official Nazi painters]. What is more important, ⑤ [art must be an end in itself for the artist], because ⑥ [the artist can do the best work only in an atmosphere of complete freedom].

Beardsley said that the conclusion in this example is statement ②. Statement ④ needs to be rewritten as a declarative sentence, e.g. "Academic monstrosities [were] produced by the official Nazi painters." Statement ① points out that the conclusion isn't accepted by everyone, but statement ① is omitted from the diagram because it doesn't support the conclusion. Beardsley said that the logical relation between statement ③ and statement ④ is unclear, but he proposed to diagram statement ④ as supporting statement ③.

A box and line diagram of Beardsley's example, produced using Harrell's procedure

More recently, philosophy professor Maralee Harrell recommended the following procedure:[13]

1. Identify all the claims being made by the author.
2. Rewrite them as independent statements, eliminating non-essential words.
3. Identify which statements are premises, sub-conclusions, and the main conclusion.
4. Provide missing, implied conclusions and implied premises. (This is optional depending on the purpose of the argument map.)
5. Put the statements into boxes and draw a line between any boxes that are linked.
6. Indicate support from premise(s) to (sub)conclusion with arrows.

Argument maps are useful not only for representing and analyzing existing writings, but also for thinking through issues as part of a problem-structuring process or writing process.[14] The use of such argument analysis for thinking through issues has been called "reflective argumentation".[15]

An argument map, unlike a decision tree, does not tell how to make a decision, but the process of choosing a coherent position (or reflective equilibrium) based on the structure of an argument map can be represented as a decision tree.[16]

From Whately's Elements of Logic p467, 1852 edition

In the Elements of Logic, published in 1826 and issued in many subsequent editions,[17] Archbishop Richard Whately gave probably the first form of an argument map, introducing it with the suggestion that "many students probably will find it a very clear and convenient mode of exhibiting the logical analysis of the course of argument, to draw it out in the form of a Tree, or Logical Division".

However, the technique did not become widely used, possibly because for complex arguments, it involved much writing and rewriting of the premises.

Wigmore evidence chart, from 1905

Legal philosopher and theorist John Henry Wigmore produced maps of legal arguments using numbered premises in the early 20th century,[18] based in part on the ideas of 19th century philosopher Henry Sidgwick who used lines to indicate relations between terms.[19]

Dealing with the failure of formal reduction of informal argumentation, English speaking argumentation theory developed diagrammatic approaches to informal reasoning over a period of fifty years.

Monroe Beardsley proposed a form of argument diagram in 1950.[12] His method of marking up an argument and representing its components with linked numbers became a standard and is still widely used. He also introduced terminology that is still current describing convergent, divergent and serial arguments.

A Toulmin argument diagram, redrawn from his 1959 Uses of Argument

A generalised Toulmin diagram

Stephen Toulmin, in his groundbreaking and influential 1958 book The Uses of Argument,[20] identified several elements to an argument which have been generalized. The Toulmin diagram is widely used in educational critical teaching.[21][22] Whilst Toulmin eventually had a significant impact on the development of informal logic he had little initial impact and the Beardsley approach to diagramming arguments along with its later developments became the standard approach in this field. Toulmin introduced something that was missing from Beardsley's approach. In Beardsley, "arrows link reasons and conclusions (but) no support is given to the implication itself between them. There is no theory, in other words, of inference distinguished from logical deduction, the passage is always deemed not controversial and not subject to support and evaluation".[23] Toulmin introduced the concept of warrant which "can be considered as representing the reasons behind the inference, the backing that authorizes the link".[24]

Beardsley's approach was refined by Stephen N. Thomas, whose 1973 book Practical Reasoning In Natural Language[25] introduced the term linked to describe arguments where the premises necessarily worked together to support the conclusion.[26] However, the actual distinction between dependent and independent premises had been made prior to this.[26] The introduction of the linked structure made it possible for argument maps to represent missing or "hidden" premises. In addition, Thomas suggested showing reasons both for and against a conclusion with the reasons against being represented by dotted arrows. Thomas introduced the term argument diagram and defined basic reasons as those that were not supported by any others in the argument and the final conclusion as that which was not used to support any further conclusion.

Scriven's argument diagram. The explicit premise 1 is conjoined with additional unstated premises a and b to imply 2.

Michael Scriven further developed the Beardsley-Thomas approach in his 1976 book Reasoning.[27] Whereas Beardsley had said "At first, write out the statements...after a little practice, refer to the statements by number alone"[28] Scriven advocated clarifying the meaning of the statements, listing them and then using a tree diagram with numbers to display the structure. Missing premises (unstated assumptions) were to be included and indicated with an alphabetical letter instead of a number to mark them off from the explicit statements. Scriven introduced counterarguments in his diagrams, which Toulmin had defined as rebuttal.[29] This also enabled the diagramming of "balance of consideration" arguments.[30]

In 1998 a series of large-scale argument maps released by Robert E. Horn stimulated widespread interest in argument mapping.[31]

The argument map tree schema of Kialo with an example path through it: all Con-argument boxes and some Pros were emptied to illustrate an example path.[32]

A partial argument tree with claims and impact votes for arguments illustrates one form of collective determination of argument weights that is based on equal-weight user voting.[33]

Human–computer interaction pioneer Douglas Engelbart, in a famous 1962 technical report on intelligence augmentation, envisioned in detail something like argument-mapping software as an integral part of future intelligence-augmenting computer interfaces:[34]

You usually think of an argument as a serial sequence of steps of reason, beginning with known facts, assumptions, etc., and progressing toward a conclusion. Well, we do have to think through these steps serially, and we usually do list the steps serially when we write them out because that is pretty much the way our papers and books have to present them—they are pretty limiting in the symbol structuring they enable us to use. ... To help us get better comprehension of the structure of an argument, we can also call forth a schematic or graphical display. Once the antecedent-consequent links have been established, the computer can automatically construct such a display for us.

— Douglas Engelbart, "Augmenting human intellect: a conceptual framework" (1962)

In the middle to late 1980s, hypertext software applications that supported argument visualization were developed, including NoteCards and gIBIS; the latter generated an on-screen graphical hypertextual map of an issue-based information system, a model of argumentation developed by Werner Kunz and Horst Rittel in the 1970s.[35] In the 1990s, Tim van Gelder and colleagues developed a series of software applications that permitted an argument map's premises to be fully stated and edited in the diagram, rather than in a legend.[36] Van Gelder's first program, Reason!Able, was superseded by two subsequent programs, bCisive and Rationale.[37]

Throughout the 1990s and 2000s, many other software applications were developed for argument visualization. By 2013, more than 60 such software systems existed.[38] In a 2010 survey of computer-supported argumentation, Oliver Scheuer and colleagues noted that one of the differences between these software systems is whether collaboration is supported.[39] In their survey, single-user argumentation systems included Convince Me, iLogos, LARGO, Athena, Araucaria, and Carneades; small group argumentation systems included Digalo, QuestMap, Compendium, Belvedere, and AcademicTalk; community argumentation systems included Debategraph and Collaboratorium.[39] Free and open source structured argumentation systems include Argdown[40] and Argüman.[41] As of 2020, the commercial website Kialo is the most widely adopted argumentation-based deliberation system.[42]

It has traditionally been hard to separate teaching critical thinking from the philosophical tradition of teaching logic and method, and most critical thinking textbooks have been written by philosophers. Informal logic textbooks are replete with philosophical examples, but it is unclear whether the approach in such textbooks transfers to non-philosophy students.[21] There appears to be little statistical effect after such classes. Argument mapping, however, has a measurable effect according to many studies.[47] For example, instruction in argument mapping has been shown to improve the critical thinking skills of business students.[48]

There is empirical evidence that the skills developed in argument-mapping-based critical thinking courses substantially transfer to critical thinking done without argument maps. Alvarez's meta-analysis found that such critical thinking courses produced gains of around 0.70 SD, about twice as much as standard critical-thinking courses.[49] The tests used in the reviewed studies were standard critical-thinking tests.

The Argument Interchange Format, AIF, is an international effort to develop a representational mechanism for exchanging argument resources between research groups, tools, and domains using a semantically rich language.[51] AIF-RDF is the extended ontology represented in the Resource Description Framework Schema (RDFS) semantic language. Though AIF is still something of a moving target, it is settling down.[52]

The Legal Knowledge Interchange Format (LKIF)[53] was developed in the European ESTRELLA project[54] and designed with the goal of becoming a standard for representing and interchanging policy, legislation and cases, including their justificatory arguments, in the legal domain. LKIF builds on and uses the Web Ontology Language (OWL) for representing concepts and includes a reusable basic ontology of legal concepts.

Argdown is a Markdown-inspired lightweight markup language for complex argumentation.[40] It is intended for exchanging arguments and argument reconstructions in a universally accessible and highly human-readable way. The Argdown syntax is accompanied by tools that facilitate coding and transform Argdown documents into argument maps.[55]