Defining and Exemplifying Wu-Lin Chen (wlchen@pu.edu.tw) Department of Computer Science and Information Management

Definition A definition answers the question, “What is it?” A definition is necessary because a word or concept sometimes has more than one meaning. a term is being used in a special way. A definition should be complete enough to include all the items in the category yet enough to eliminate items that do not belong.

Definition Most definitions by their nature are imperfect, so writers use them in a provisional way. A good definition should include the general classification of a term plus the specific characteristics that differentiate the term from other members of its class. A good definition should be thoughtful and accurate, but don’t have to be exhaustive. Definitions are just like road signs to tell your readers what you mean. Good road signs are never cluttered and should point the way clearly.

Type of Definition Logical definition Definition by negation Operational definition Definition by description Definition by metaphor Definition by quotation

Logical Definition A logical definition distinguishes an item from others like it. A beret is a cap that is flat, round, and usually made of felt. Plague is a disease that is a persistent epidemic. A friend is a person to whom we feel close.

Definition by negation Definition by negation says what something is not. FM radio is the opposite of AM. Chinese is not at all like English. A friend won’t let you down.

Operational Definition Operational definition tells how something works or what it is used for. A rolling pin is for flattening dough. A Dutch door lets the outside air in but keeps animals out. A friend will be there when you need her.

Definition by Description Definition by description mentions some of the observable attributes of an item. A penguin is a bird with short wings and webbed feet. A clarinet is a long, black woodwind instrument with a flare at the end. A friend is someone who really talks to you.

Definition by Metaphor Definition by metaphor compares one thing to another. War is hell. The Midwest is America’s breadbasket. A friend is one’s greatest treasure.

Definition by Quotation Definition by quotation uses the well-put words of others to define: “Old men are children for a second time.” ― Aristophanes “Ambition, the soldier’s virtue.” ― Shakespeare “A fool at forty is a fool indeed.” ― Edward Young

Definition and Your Audience Respect your readers. Do not confuse them with undefined terms. Suit definitions to particular audiences.

Using English To Define Definition formula: Term = Class + Characteristics EX: A giraffe is an animal which is a tall, African animal with a very long neck. The characteristics often appear as a relative clause beginning with which, that, who, or where.

Using English To Define Definition formula: Term = Class + Characteristics EX: Chemical energy is potential energy that is stored in gasoline, food, and oil. Term = chemical energy Class = potential energy Characteristics = that is stored in gasoline, food, and oil EX: Mechanical energy is energy related to the movement of objects. Term = mechanical energy Class = energy Characteristics = (that is) related to the movement of objects The characteristics often appear as a relative clause beginning with which, that, who, or where.

Using English To Define Use the form of an infinitive phrase or prepositional phrase to express the characteristics Term = Class + Characteristics EX: Energy is the ability to do work. … Kinetic energy is the energy of motion. Term = energy Class = ability Characteristics = to do work (Infinitive Phrase) Term = kinetic energy Class = energy Characteristics = of motion (Prepositional Phrase)

Using English To Define If there is more than one way to define something, the modal of possibility may is used. EX: Thermal energy may be defined as the kinetic energy of molecules. Term = thermal energy Class = kinetic energy Characteristics = of molecules

Using English To Define The characteristics could precede the class EX: Potential energy is stored energy. Term = potential energy Characteristics = stored Class = energy

Using English To Define Definitions require the present simple tense and the verb to be. The definite article, the, is usually not used with the term being defined because definitions are general statements.

Specific characteristics Sentence Patterns Term = General Class Word + Specific characteristics who that by which where An astronomer A barometer Conduction A laboratory a scientist an instrument a process a place studies the universe. measure air pressure. heat is transferred. experiments are performed. is Physics A volt the study a unit of matter and energy. for measuring electrical pressure. is

Sentence Patterns (cont.) Term = Specific characteristics + General class word Mercury A triangle Asbestos A dinosaur A monkey liquid three-sided fire-resistant prehistoric small, long-tailed metal. plane figure. mineral. reptile. primate. is a

Writing Skills A definition may be done as little as a sentence or a much as a book. Use an extended definition to help define a complex concept. An extended definition includes the basic parts of a formal definition as well as additional information that may includes description, examples, classification, comparison, explanation, or other details.

Exemplifying A picture is worth a thousand words. One example is worth a thousand explanation. An example brings the general or abstract statement down to a specific or concrete image. An example adds impact, making the statement more memorable, more interesting, and more persuasive, and providing evidence for it. Scientists use examples to explain or clarify a concept and to give evidence to support it. Examples serve to test the validity of a point. If no example can be found to illustrate a point, there may not be a point.

Using English to Exemplify Examples make a point clearer and at the same time, give evidence to support it, EX: The physical states of a substance is affected by its temperature. For example, at a temperature of 0 ° C or below, water is a solid (ice); above 0° C it becomes a liquid; and at 100 ° C it turns to a gas (steam).

Using English to Exemplify An example may comprise a few words, a sentence, a paragraph or more. EX: Temperature alters the color of matter. Iron, for example, turns red, then orange, and then white at increasingly higher temperatures.

Using English to Exemplify Examples are not always marked with clue words such as for example, for instance, and to illustrate. Examples can sometimes be identified by the context of the paragraph. EX: The size of an object is affected by temperature. A glass may break when boiling water is poured into it… EX: Temperature also affects the pressure of a gas. If a closed glass tube is heated, the increased pressure inside will cause it to break.

Using English to Exemplify Use more than one example to explain the various aspects of a concept. EX: Living things are very sensitive to comparatively small temperature changes. This is exemplified when we touch something very hot or cold and feel pain. … We pasteurize milk and cook meat to kill harmful bacteria and other organisms that cannot tolerate heat.

Sentence Patterns For example, For instance, To be specific, To illustrate, iron turns red when it is heated. for example, for instance, Iron, turns red when heated. an example a case an instance an illustration of a substance that turns red when heated. Iron is

Sentence Patterns exemplifies illustrates Iron the concept of heat affecting color. exemplified illustrated The concept of heat affecting color is by iron. such as like Solids iron and copper turn red when heated.

When Writing Examples Examples in science are usually written in the present simple tense. Examples are also used to illustrate terms, and these examples are similar to classification. Examples are not always marked with clue words and often can only be identified by context of the paragraph.

Writing Skills Use examples to make your topic sentence clear and memorable. Examples enable reader to understand the topic sentence even if they do not know the meaning of some unknown terminologies.