Arguments from Definition
Lesson 4 - Master the Academic Essay
In lesson one, I introduced the thesis statement. The focus of lesson two was a philosophy of research. And, in lesson three, I addressed to fundamental methods for doing good research.
Now that we’ve determined that the thesis is the basis of our argument, an argument that can only be discovered out of a good research philosophy, and there are fundamental research methods that are profitable for discovering what can be argued, we now turn to the objective of this lesson—definition.
For those attentive to the list of questions in the Stasis Theory presented in the last lesson, you may remember the second kind of question in discovering what can be argued is “What is it?”—the definition questions. Cicero notably claimed that in order to understand the significance of a thing we have to know the attributes that are being ascribed to the thing.1 Sister Miriam Joseph, in her acclaimed book, The Trivium, remarks that “Definition makes explicit the intension or meaning of a term, the essence that it represents.”2
The tendency of the majority of students to whom I teach academic writing is to “Google” a word and grab the first definition that populates. In some rare cases, they may pull a physical dictionary off the bookshelf; yet, they often do the same thing. But, as C. S. Lewis noted in his book, Studies in Words, “We are often deceived. In an old author the word may mean something different. I call such senses dangerous senses because they lure us into misreadings.”3
One’s instinct might be to assume the reader understands what the writer means by a word and can “look it up” if not. But defining our terms is essential, not only for keeping everyone on the same page, but also as one of the most powerful arguments writers can make. Defining terms accurately and effectively establishes the boundaries of what needs to be proved and what doesn’t. It also means implicitly governing the nature and direction of the arguments supporting your thesis.
Trusting I have convinced you that definitions matter greatly, we can now turn to exploring the various kinds of definitions:4
Definition by Example:
This is the most informal type of definition and is not usually specific enough for most technical arguments. However, there are cases where it might be helpful to illustrate what you mean by pointing to an example.
Example: “A hotrod is that ‘57 Chevy Bel Air your dad has stored in your garage.”
Definition by Logic:
A logical definition expresses a thing’s essence by naming its genus (general category) and species (specific difference).
Example: “A human being is a rational animal.” Or, “A triangle is a three-sided polygon.”
Definition by Distinction:
A distinctive definition names a things by its essence and a property. In other words, its species is its genus (general category) plus property (an accident extending from its essence but not its essence.
Example: “Mankind is a being capable of sadness.” Here sadness is a property of man’s rational essence. Sadness is not his essence but he can only be sad because he can reason.
Definition by Operation:
An operational definition defines a thing apart from its essence. Instead it defines its nature or type by the observable effects or the measurable results either that it produces or that occurs in its presence.
Example: “Temperature is what a thermometer reads.” Or, “Learning is a measurable change in behavior following the relevant training.”
Definition by Cause:
A causal definition is similar to an operational definition but names the cause—any of the four causes: efficient, material, formal, final—which produced the reality the word being defined signifies.
Example: “A statue is a clay or stone formation created by a sculptor’s artistic craftsmanship.” Or, “An essay is a composition of a writer’s argument expressed with wisdom and eloquence.”
Definition by Description:
A descriptive definition is simply a careful enumeration of a thing’s characteristics.
Example: “A book is an object composed of written papers arranged for easy reading and bound on one side, between two covers.” Or, “A cat is a small four-footed animal covered in soft hair, usually with a long tail, pointed ears, whiskers, and sharp teeth, often domesticated as a family pet.”
Definition by Etymology:
An etymological definition is one that is obviously based on a word’s derivation. For example: Education derives from the Latin: educare / educere: e- (“out of”) + ducere (“to lead”). Thus, the literal sense of education is “to lead out.” But it must be noted that etymological definitions are notoriously problematic because a word’s present meaning often does not adhere to its etymological meaning.
Example: The English word nice means “pleasant; agreeable; satisfactory” according to the Oxford Languages Dictionary. But its etymology has an incredibly interesting story. According to the same Oxford Languages Dictionary, it derives from the Latin: nescire and nescius, which mean “to not know” and ignorant” respectively. It entered Middle English as ‘stupid’. It gave rise to ‘fastidious’ and ‘scrupulous’, which eventually led to the sense ‘fine’ and ‘subtle’, and to the main current senses of “pleasant; agreeable; satisfactory.”
Definition by Synonym:
Synonymous definitions are illustrative of the similar or near equivalent meanings words can symbolize. These too are helpful in the way Definitions of Example can be casually helpful. But synonyms always differ in nuanced ways, “usually either in the logical or in the psychological dimensions or in both.”5
Example: “His wife was frugal, but not stingy.” Or, “His wife turned their house into a home.” Even though we often use these examples interchangeably, in the first example, frugal is a virtue and stingy is a vice; and, in the second example, the house is a material structure and the home is relationally qualitative.
Even after doing the careful work of establishing definitions that are foundational to our arguments, it is essential that a writer recognize there are some important terms which will defy any of these definitional approaches. Such terms are usually technical or legal jargon that require a de facto or arbitrary definition established by some entity’s use of the term. For example, words like “larceny”or “resident” will be defined by various states or government agencies for legal purposes. In those cases, it’s necessary to rely on the documents defining those terms for definitional sources.
Cicero, De Oratore, I.42
Sister Miriam Joseph, The Trivium: The Liberal Arts of Logic, Grammar, and Rhetoric, 79.
C. S. Lewis, Studies in Words, Second Edition. (New York: HarperOne, 2013), 11.
Gregory Roper, Mastering the Four Arguments, 28-29 and Joseph, The Trivium, 79-83.
Joseph, The Trivium, 83.



