The word example has two main meanings:

  1. Way of being or doing worthy of imitation: setting an example, leading by example, being an example for the community.
  2. Any item in a series of equivalent elements, one case among others. If the series is composed of different elements, a typical example is the most characteristic individual, central to the series.

Besides the specific forms of argumentation described below, the following forms of argumentation are related with the example: S. Exemplum; Imitation; Ab exemplo.

1. The example in the Aristotelian rhetorical system

In a version of the Aristotelian rhetorical system, the induction and the syllogism are the instruments of scientific discourse, whereas the example and the enthymeme are their counterparts in rhetorical discourse (Rhet, II, 20, 1393a20-25, RR p. 335). There are different kinds of examples:

[Argument by example] has two varieties; one consisting in the mention of actual past facts, the other in the invention of facts by the speaker. Of the latter, again, there are two varieties, the illustrative parallel and the fable. (Id., 1393a25-30; RR p. 357-358)

A table of rhetorical instruments:

An argument drawn from an example based on past, real facts is illustrated by a form of induction leading to the conclusion, “we must prepare for war against the King of Persia and not let Egypt be subdued”, in view of two past experiences which were detrimental to the Greeks:

For Darius of old did not cross the Aegean until he had seized Egypt; but once he had seized it, he did cross. And Xerxes again did not attack us until he had seized Egypt. but once he had seized it, he did cross. (Rhet., II, 20, 1393a30-b5, RR p. 335)

The reasoning can be seen as an induction, aimed at establishing as a law that “the conquerors who seize Egypt then cross the sea to Europe”, or as a direct stimulation to wake up bad memories. In that case, the argument by example would function as a kind of two-term reasoning.

Comparison — Aristotle gives as an example of a “parable”, an analogy drawn from the speeches of Socrates. This parable condemns the practice of drawing lots for magistrates, since one does not “use the lot to select a steersman from among a ship’s crew” (Rhet., II, 20, 1393b5, RR, p. 335); S. Metaphor.

Fable — Aristotle gives as an example of a fable of the horse that wanted revenge on the stag, and in so doing becomes a slave to man, with an application to the saviors of the fatherland who quickly became tyrants (Rhet, II, 20, 1393a5-25, RR p. 337). As portraits (S. Ethos), fables are a fully argumentative and literary genre, from Aesop (620 – 564 BCE) to modern times, S. Exemplum.

2. Argument by example

As a generalization (induction) based on a single specific case, the argument from example draws on an observation made on one individual, and categorically generalizes it to all individuals of the same class or of the same name:

This butterfly is blue, so (all) butterflies are blue.

In reality it is only possible to conclude “some Bs are P” from “this B is P”. The generalization on the basis of one single specific case corresponds to the converse of the instantiation of a universal proposition, which is valid; if “all Is are P” then “this I is P”.

This swan is white, it’s okay, since (all) swans are black.

Argument by example is a kind of hasty generalization or induction on the basis of a single case, or a relatively small number of cases. It may also be a case of two-term reasoning.

The inductive narrative proceeds from an anecdote: “the owners of iPhones are unbearable. Recently I was camping…” and the anecdote develops, highlighting the terrible behavior of one iPhone user and generalizes this case to all iPhone users. In Aristotelian terms, the process is an inductive generalization, based on a real past fact, which is then elaborated as a truth revealing fable.

3. Argumentation from a generic example, or ecthesis

A generic example is a being in which all the properties of the genus to which it belongs are clearly manifested. It is a prototype of the class, its best incarnation, S. Category; Intra-categorical Analogy. The argument from the generic example is based on such a specimen and results in conclusions being made about a given genus (about all the individuals belonging to that genus):

The generic example consists in explaining the reasons for the validity of an assertion by performing operations or transformations on a given concrete object, considered not for itself but as a characteristic representative of a class. (Balacheff 1999, p. 207).

The process is also known as ecthesis, defined as “[a] technique of demonstration used especially in Euclidean geometry: to establish a theorem, you reason on a singular figure. Your inference is correct if it does not mention the characteristics peculiar to the drawn figure but only those which it shares with all the figures of its species.” (Vax 1982, Ecthèse)

4. Exemplification of a generic or accidental feature?

The argument by example is a legitimate extrapolation if it is founded on a generic feature. If one asks for example how many wings birds may have, observation of any bird will lead the observer to discover the correct answer. On the other hand, if one asks about the average weight of a pigeon, the same procedure is absurd: “this pigeon taken at random weighs 322 g. So the average weight of a pigeon is 322 g.

As in many cases, it is not previously known whether the investigated feature is essential or accidental, this distinction is exploited as an argumentative resource. The proponent considers that generalization is valid because it is based on an essential trait, and the opponent argues that it is accidental and cannot be generalized. S. Classification; Accident.

The remains of a single animal belonging to an unknown disappeared species provides a wealth of knowledge about this species, but its specific conditions must be duly acknowledged, as shown by the case of the Neanderthal man.

1. The views the scientists hold about the Neanderthals have changed over time. (after G. Burenhult, “[Towards Homo Sapiens]”, 1994[1])
More precisely: Is the Neanderthal man our ancestor or a species different from our own?

2. First answer: The Neanderthal man belongs to our species. “It has long seemed obvious that the physical appearance of the Neanderthal man — and especially those living in Europe — was very different from ours”. However, “in spite of these physical differences, Neanderthals have long been regarded as direct ancestors of the present man” (id., p. 66).

Second answer: The Neanderthal man belongs to a different species. “Following the work of the French paleontologist Marcellin Boule these differences were judged too great” (id., p. 67), and the Neanderthal man was considered to belong to a different species.
The Neanderthal of Marcellin Boule: “From 1911, the paleoanthropologist Marcellin Boule published a detailed study of the skeleton. He built an image that has conditioned the popular perception of Neanderthal man for more than thirty years. His interpretations are strongly influenced by the ideas of his time concerning this extinct hominid. He describes him as a kind of savage and brutal caveman, dragging his feet and not able to walk upright.”
“Marcellin Boule describes a Neanderthal with a flattened skull, a curved vertebral column (much like gorilla), semi-flexed lower limbs and large divergent big toes. This description is in keeping with the ideas of the time on human evolution” (Wikipedia, Marcellin Boule).

4. But this Neanderthal was seriously handicapped: “In 1913, Marcellin Boule exaggerated the differences with us, not realizing that the skeleton he was studying — the “Old Man of the Chapelle aux Saints” (Corrèze, France) — was deformed by arthritis, as demonstrated by W. Strauss and A. J. Cave in 1952.” (id., p. 67)
“J.-L. Heim describes the subject as badly disabled; he suffered a deformity of the left hip (epiphysiolysis or rather trauma), a crushing of the finger of the foot, severe arthritis in the cervical vertebrae, a broken rib, and a narrowing of the channels of the spinal nerves.” (Wikipedia, id.)

5. Conclusion: Our cousin, the Neanderthals: “Today Neanderthal men are seen as our cousins ​​rather than as our ancestors, although they look like us in many respects” (ibid.).

5. Exemplification as illustration and test case example

The generic example functions as a basis for an abductive generalization, resulting in a rule or regularity about a class of cases or individuals. Specific cases can be introduced in relation with such a general discourse.

— The illustrative example facilitates the understanding of a concept or a law, by introducing a (typical) instantiation of the concept or the law:

A migratory bird is a bird that … So the swallow…

Moreover, if the example chosen is (presented as) typical of the phenomenon, it renders the time-consuming and precarious work of checking a large number of cases unnecessary. In this sense, to give an argument in defense of a general statement is simply to find a case to which it applies correctly. If the general statement is the result of an a priori argumentation or illumination, the illustrative example will at least show that the conclusion is not undermined by the first example that comes to mind (see infra, § 6).
The illustrative example can also be used as an epideictic amplification technique:

Whereas an example is designed to establish a rule, the role of illustration is to strengthen adherence to a known and accepted rule, by providing particular instances which clarify the general statement, show the import of this statement by calling attention to its various possible applications, and increase its presence to the consciousness. (Perelman & Olbrechts-Tyteca [1958], p. 357)

— The test case example is different. It may be introduced as an objection to the theory, and the speaker must show that the general principle he or she favors can be successfully applied to this case, that it accounts for this case.

6. Refutation by the counter-example (arg. in contrarium)

An example does not establish a law, but is sufficient to refute a generalization. Argument by the counterexample is the standard method of refutation of general propositions “all A are B”: this assertion is refuted by showing an A which is not B. This strategy is perfectly operative in ordinary argument, S. Opposites.

[1] G. Burenhult, Vers Homo Sapiens. In Le Premier homme. Preface by Y. Coppens, Paris, Bordas, 1994, p. 67.