The previous chapter examined methods for constructing and evaluating arguments. Presenting sound reasoning effectively requires clear, accurate, and understandable language, as correct reasoning can only be conveyed through language. The clarification and analysis of terms and statements are central objectives of philosophy in general and logic in particular.
To interpret, analyze, and evaluate arguments effectively, close attention to language is crucial. Many logical errors and misunderstandings stem from careless or imprecise language use. Logic, therefore, demands the proper use of terms and statements. This chapter explores the relationship between logic and language, focusing on the functions of language, the meaning and definition of terms, and various definition techniques. We will cover an overview of the philosophy of language, the formal meaning of words, defining concepts, intension and extension of terms, types and purposes of definitions, criteria for lexical definitions, and using definitions to evaluate arguments.
Upon successful completion of this chapter, you will be able to:
Philosophy of Language involves reasoned inquiry into the nature, origins, usage, and cognition of language, as well as the relationship between language and reality. Language itself can be understood as a system of standardized meanings for symbols (words, sounds, gestures) used in consistent patterns for communication, allowing expression of feelings, thoughts, and desires. This section provides an overview of the philosophy of language, including its meaning, nature, history, key debates, and major philosophical approaches to the concept of meaning.
After completing this section, you will be able to:
Activity # 1:
What do you understand the philosophy of language to be?
A fundamental question in the Philosophy of Language is "What is language?" From the perspective of semiotics (the study of sign processes and meaning construction), language involves manipulating and using symbols to refer to signified content.
More broadly, Philosophy of Language conducts reasoned inquiry into the origins of language, the nature of meaning, language use and cognition, and the relationship between language and reality. As a distinct discipline, it addresses questions such as: "What is meaning?", "How does language refer to the world?", "Is language primarily learned or innate?", and "How does sentence meaning arise from word meanings?"
Philosophy of language should be distinguished from Linguistics. Linguistics focuses on empirical questions about specific languages: What distinguishes English from other languages? What are the structural differences between Spanish and French?
Linguists, such as Noam Chomsky (a defining figure in 20th-century linguistics), emphasize grammar and syntax (rules governing sentence structure) as core characteristics of language. Chomsky proposed that humans possess an innate understanding of "universal grammar"—a set of shared linguistic principles. Exposure to a particular language, he argued, triggers this pre-existing knowledge. Chomsky's approach studies "I-languages" (internal, individual linguistic competence based on generative rules), partly motivated by the belief that principled distinctions between specific languages are difficult to draw clearly. Alternative approaches, termed "E-languages," attempt to explain language based on usage within specific speech communities and defined sets of well-formed utterances.
Issues of translation and interpretation raise further challenges for philosophers of language. Some argue that the meaning of a word or sentence cannot be understood in isolation but only in relation to a larger segment of language, or even the entire language. This perspective is known as Semantic Holism, which posits that meaning is fundamentally holistic rather than atomistic (associated with individual units).
In the Western tradition, foundational work on language was undertaken by Plato, Aristotle, and the Stoics in Ancient Greece. Plato explored the idea that names might be naturally determined, with basic sounds (phonemes) representing fundamental ideas, though he acknowledged a role for convention.
Aristotle investigated how the meaning of predicates (terms describing subjects) arises from abstracting similarities among individual things. This view anticipates later theories of Nominalism (universals are just names). However, his belief that these similarities reflect a real, shared form also aligns him with moderate Realism (universals have some real existence).
The Stoic philosophers significantly contributed to grammatical analysis, identifying parts of speech (nouns, verbs, etc.). Their concept of the lektón—the meaning or sense of a term, distinct from the term itself—introduced the crucial notion of a proposition as the content of a sentence that can be true or false.
Medieval Scholastic philosophers showed great interest in language, partly driven by the need to translate Greek texts. Treating Logic as a "science of language," they explored issues like vagueness and ambiguity, the doctrine of supposition (how a term's interpretation varies with context), and the distinction between categorematic (meaningful on their own) and syncategorematic (meaningful only with others) terms.
Renaissance linguists explored the concept of a philosophical or universal language, inspired by encounters with non-alphabetic writing systems like Chinese characters and Egyptian hieroglyphs.
The philosophical study of language gained prominence in Western philosophy during the late 19th and 20th centuries, particularly within Analytic Philosophy, where some viewed philosophy itself as fundamentally concerned with language analysis. This shift is often referred to as the "linguistic turn."
In summary, philosophy of language investigates the nature, origins, and use of language. Analytic philosophers typically focus on four central problems: the nature of meaning, language use, language cognition, and the relationship between language, logic, and reality. In contrast, Continental philosophers often integrate the philosophy of language into broader discussions within logic, hermeneutics, phenomenology, and other fields.
The question "What is meaning?" is complex. Generally, meaning can be understood as the content conveyed by words or signs during communication.
A distinction is often made between conceptual meaning (the literal or dictionary definition of words, analyzable through semantic features) and associative meaning (the individual mental understandings, connotations, and emotional responses evoked by words, which can be subjective and context-dependent).
Several major philosophical approaches address the nature of meaning:
Language comprises standard word meanings and forms of speech used for communication, expressing thoughts, feelings, and desires through patterned symbols (words, sounds, signs). Language serves many purposes, acting as a tool for communication, expressing ideas, conveying information, and evoking emotions.
This section focuses on language functions relevant to logic, particularly the distinction between conveying information (cognitive meaning) and expressing feelings (emotive meaning). We will explore the intensional and extensional meanings of terms, which are crucial for understanding definitions and evaluating arguments clearly.
After completing this section, you will be able to:
Activity # 1:
What functions of language are you aware of? How do you understand the difference between cognitive and emotive meanings?
As discussed previously, arguments are composed of statements, which are declarative sentences. Sentences are built from words, and words convey meaning, often clarified through definitions.
Therefore, words are fundamental units of language and crucial components of arguments. Understanding how language functions is vital for logic.
Ordinary language serves numerous functions in daily life. The philosopher Ludwig Wittgenstein suggested these functions are virtually unlimited. Language is used to:
Ask questions
Tell stories
Tell lies
Guess answers
Form hypotheses
Make promises
Tell jokes
Flirt
Give directions
Sing songs
Issue commands
Greet someone
Express emotions
Persuade
Define terms
For logical purposes, two functions are particularly important: (1) conveying information and (2) expressing or evoking feelings. Consider the following examples:
Example 1 (Primarily Informative):
The death penalty, legal in thirty-six states, has been carried out most often in Georgia; however, since 1977, Texas holds the record for the greatest number of executions.
Example 2 (Primarily Emotive/Expressive):
The death penalty is a cruel and inhuman form of punishment in which hapless prisoners are dragged from their cells and summarily slaughtered only to satiate the bloodlust of a vengeful public.
These examples illustrate how different language choices achieve different primary functions.
Example 1 primarily conveys factual information. Example 2 primarily expresses or evokes strong feelings about the death penalty. This difference arises from the terminology used.
Terminology primarily conveying information has cognitive meaning. Terminology primarily expressing or evoking feelings has emotive meaning.
In Example 1, words like "legal," "thirty-six," "record," and "executions" have primarily cognitive meaning. In Example 2, words like "cruel," "inhuman," "hapless," "dragged," "slaughtered," "bloodlust," and "vengeful" carry strong emotive meaning. Importantly, these emotive words often *also* have cognitive meaning (e.g., "cruel" means tending to cause pain). However, their primary impact in this context is emotional.
The second example (emotively charged statement about the death penalty) highlights two important points for logical analysis:
A value claim asserts that something is good, bad, right, wrong, better, worse, more important, or less important. The emotive statement about the death penalty (Example 2) implicitly asserts the value claim that the death penalty is morally wrong.
Such value claims are often the most significant part of the cognitive meaning within emotive statements. For logical analysis, it is essential to:
People often use emotive terminology strategically. Value claims typically require supporting evidence (e.g., arguing *why* the death penalty is immoral). Emotive language, however, can simultaneously make a value claim and provide psychological impetus for accepting it, often bypassing the need for evidence. Readers or listeners might be swayed by the emotional force and accept the value claim without critical evaluation.
Furthermore, speakers or writers might resort to emotive terms ("crazy," "stupid," "brilliant") when they want to express a value judgment but lack or are unwilling to provide supporting reasons. It serves as a shortcut, often substituting emotional appeal for logical justification.
Within arguments, emotive terminology functions similarly: it allows arguers to embed value claims without explicit evidence and lends the argument persuasive force, potentially overwhelming critical thinking. This "steamroller effect" can obscure logical flaws.
To counter this, one must actively disengage the cognitive content (including value claims) from the emotive language. Rephrasing the argument using neutral terms and making implicit value claims explicit allows for clearer logical evaluation.
Example:
Now that we know that the rocks on the moon are similar to those in our backyard and that tadpoles can exist in a weightless environment, and now that we have put the rest of the world in order, can we concentrate on the problems here at home? Like what makes people hungry and why is unemployment so elusive?
This argument implicitly concludes that government funds spent on space exploration and international actions should be redirected to domestic problems. The emotive language downplays the space program (comparing moon rocks to backyard rocks, focusing on tadpoles) and exaggerates international efforts ("put the rest of the world in order"). It uses dismissive or trivializing language to influence the audience's perception of priorities.
Rephrasing the previous argument in neutral language, making implicit claims explicit:
Premise 1 (Implicit/Value): The knowledge gained from space exploration (e.g., lunar geology, effects of weightlessness) is relatively insignificant compared to domestic issues.
Premise 2 (Implicit/Value): Domestic problems like hunger and unemployment are more important than space exploration.
Premise 3 (Implicit/Exaggerated): U.S. international efforts have successfully resolved major global problems.
Premise 4 (Implicit/Value): Past international efforts addressed problems less important than current domestic ones.
Conclusion: Therefore, funds previously allocated to space exploration and international actions should be redirected to solve domestic problems.
This neutral reformulation allows for clearer evaluation. We can now assess the truth of the premises (several seem questionable or false, e.g., P1, P3) and the strength of the inference. The original emotive language obscured the weakness of the underlying claims. Even if rephrased with factually accurate premises (e.g., "Part of the space program involved studying lunar rocks"), the argument's support for the conclusion might still be weaker than initially perceived due to the removal of emotional weight.
Having distinguished cognitive from emotive meaning, we now examine two common problems that affect cognitive meaning and hinder clear communication and logical analysis: vagueness and ambiguity.
An expression is vague if it lacks a precise meaning, resulting in borderline cases where it's unclear whether the expression applies. Vague terms often allow for a continuous range of interpretations; their meaning is hazy or imprecise.
Examples of vague words include: "love," "happiness," "peace," "excessive," "fresh," "rich," "poor," "normal," "conservative," "tall," "hot," "bald." It's often difficult to determine the exact point at which something qualifies (e.g., how rich is "rich"? how bald is "bald"?).
Vagueness can also affect entire statements due to word combinations. For instance, "Today our job situation is more transparent." What does "job situation" encompass, and what does "transparent" mean in this context? The overall meaning is unclear.
However, not all vagueness is problematic. In ordinary conversation, terms like "tall" might be perfectly adequate. Vagueness becomes an issue when the level of precision required by the situation is lacking, potentially leading to misunderstandings or flawed reasoning.
An expression is ambiguous when it can be interpreted as having two or more distinct, clearly defined meanings within a given context.
Examples of potentially ambiguous words include: "light" (color, weight, calorie count), "bank" (financial institution, river side), "mad" (angry, insane), "stress" (emphasis, psychological pressure), "right" (correct, direction, entitlement). If someone describes beer as "light," the specific intended meaning isn't immediately clear without context.
Ambiguity can also arise from sentence structure (syntactic ambiguity), not just individual words.
The key difference:
• Vagueness involves a *blur* of meaning, allowing a continuous range of interpretations with unclear boundaries.
• Ambiguity involves a *mix-up* of multiple, distinct, clear meanings.
An expression might be ambiguous between several distinct meanings, and one or more of those distinct meanings might *also* be vague. For example, "slow" could ambiguously mean mentally challenged or physically unhurried. If it means physically unhurried, that concept itself is vague (how unhurried is "slow"?).
Both vagueness and ambiguity can interfere with clear communication and logical reasoning, often leading to disputes.
Vagueness and ambiguity often contribute to disagreements or disputes between individuals. Analyzing these disputes helps illustrate the importance of clear language.
Consider these examples to understand different types of disputes:
Example 1:
Kassa: Mrs. Zenebech abuses her children. I saw her spank one of them yesterday after the child misbehaved.
Jemal: Don’t be ridiculous. Kids need discipline. By disciplining her children, Mrs. Zenebech is showing love.
This dispute likely stems from the vagueness of "abuse" versus "discipline." Where does appropriate discipline end and abuse begin? The line is unclear. Without clarifying how each person understands these terms, the dispute cannot be effectively resolved. They might agree on the facts (a spanking occurred) but disagree on how to categorize it due to the vague terms.
Example 2:
Mullu: I'm afraid Dagim is guilty of cheating on the exam. He confessed to me last night that he sat near Tsedale, the top student, and copied almost all her answers.
Worku: No, you're mistaken. In this country, no one is guilty until proven so in a court of law, and Dagim hasn't even been formally accused.
This dispute arises from the ambiguity of the word "guilty."
In Example 2, Mullu uses "guilty" in a moral sense (having committed a wrongful act), while Worku uses it in a legal sense (having been convicted by a court). Because they are using the same word with different meanings, their disagreement isn't necessarily about the facts (whether Dagim copied) but about the *term* "guilty."
Disputes arising from misunderstandings about the meaning of language (due to ambiguity or vagueness) are called verbal disputes. Often, these can be resolved by clarifying the meanings of the key terms involved.
In contrast, factual disputes arise from disagreements about the actual facts of a situation. Resolving factual disputes typically requires investigating evidence, not just clarifying language.
When analyzing a dispute, first determine if it's primarily verbal, factual, or a combination. If verbal, identify whether the root cause is ambiguity or vagueness.
Logic's main task is argument evaluation. This often requires clarifying the meaning of words within arguments, especially when vagueness or ambiguity arises. Supplying definitions is key. Therefore, understanding meaning and definition is crucial for logic. This section delves deeper into linguistic meaning, focusing on terms.
Words are the basic units of language. Our focus here is on terms: words or groups of words that can function as the subject of a statement. Terms include proper names, common names, and descriptive phrases.
Proper Names
Abebe
Ethiopia
The Blue Nile
Girma Gamachu
Common Names
animal
city
person
house
Descriptive Phrases
the first Prime Minister of Ethiopia
author of *Oromay*
those who study hard
the book on the table
Words that are not terms include verbs (e.g., "runs"), non-substantive adjectives (e.g., "quickly" used adverbially), prepositions (e.g., "above"), conjunctions (e.g., "and"), and meaningless arrangements of words. These cannot serve as the subject of a statement.
It's crucial to distinguish between *using* a word and *mentioning* a word. Any word, when mentioned (typically indicated by quotation marks or italics), can become the subject of a statement about the word itself.
Example:
• The word "wherever" (a non-term) is *used* in: "I will follow you wherever you go."
• The word "wherever" is *mentioned* in: "'Wherever' is an eight-letter word." Here, the subject is the quoted word, not the word used with its typical function.
When identifying terms, ensure the word or phrase can be *used* as the subject of a meaningful statement, not just mentioned as a linguistic object.
Words function as symbols, and the entities they symbolize are their meanings. Terms, as specific types of symbols, possess two kinds of meaning:
A term *connotes* its intension and *denotes* its extension.
Example: For the term “cat”:
• Intension/Connotation: The attributes of being feline, furry, four-legged, typically domesticated, etc.
• Extension/Denotation: The set of all actual cats (past, present, future).
Note on Terminology: "Intension" and "extension" are roughly equivalent to the modern philosophical terms "sense" and "reference." Logic's use of "connotation" (attributes defining a term) differs from its grammatical use (suggested or implied emotional associations).
Subjectivity can affect connotation (e.g., "cat" might connote "cuddly" to one person, "obnoxious" to another). To manage this, logicians focus on conventional connotation: the commonly understood attributes associated with a term by competent language speakers. This provides a more stable, shared understanding of intension.
A term's denotation (the set of things it refers to) is typically stable, but can change over time. The denotation of "currently living cat" fluctuates as cats are born and die. The denotation of "cat" (all cats ever) is arguably constant.
Some terms denote things that no longer exist or never existed. Terms like "dodo bird" or "current king of France" once denoted actual entities but now have empty extension. They denote the empty (or null) class—a class with no members.
Crucially, even terms with empty extension still possess intension (connotation). We understand the attributes of a "unicorn" (horse-like, single horn) even though none exist. This understanding allows us to know its extension is empty.
The fact that terms with empty extension still have intension highlights a fundamental relationship: intension determines extension. The attributes (intension) associated with a term serve as the criteria for identifying which things belong in the class denoted by the term (extension).
Because we understand the intension of "unicorn" (the defining attributes), we can determine that its extension is empty (no existing things match those attributes). Similarly, the intension of "cat" allows us to identify which creatures are cats and which are not.
Proper names (e.g., "Abebe") seem to pose a challenge to the "intension determines extension" rule, as they directly denote individuals seemingly without connoting specific attributes universally.
Philosophers offer different solutions. One view treats proper names as shorthand for definite descriptions or bundles of descriptions (e.g., "Abebe" might mean "the first-year Civil Engineering student since 2005 E.C." or "the class representative for this section"). The description(s) provide the intension.
Another view (causal theory of reference) suggests the intension of a proper name involves the historical chain of usage linking the name's initial assignment (e.g., at baptism) to its current use within the linguistic community. This causal chain connects the name to its referent. Regardless of the specific theory, for logical purposes, we assume that all terms, including proper names, have some form of intension that determines their extension.
The concepts of intension and extension allow us to order series of related terms:
Consider the terms: animal, mammal, feline, tiger.
Increasing intension (more specific):
animal → mammal → feline → tiger
Increasing extension (larger class size):
tiger → feline → mammal → animal
Decreasing intension (less specific):
tiger → feline → mammal → animal
Decreasing extension (smaller class size):
animal → mammal → feline → tiger
These examples illustrate a common pattern: increasing intension usually corresponds to decreasing extension, and vice versa.
The inverse relationship between intension and extension doesn't always hold, particularly with terms having empty extension or terms where adding attributes doesn't change the set of things denoted.
Example (Empty Extension):
unicorn → unicorn with blue eyes → unicorn with blue eyes and a green horn
Here, intension increases (more attributes), but extension remains constant (empty class). It doesn't decrease.
Example (Constant Extension):
living human being → living human being with a genetic code → living human being with a genetic code and a brain
Intension increases, but since all living humans have genetic codes and brains, the extension (the set of all living humans) remains the same. Again, extension does not decrease as intension increases.
Arguments are built from statements, statements from words, and the meanings of words are often clarified through definitions. A definition provides a structured explanation of a term's meaning. Effectively crafted definitions are vital for clear communication and resolving verbal disputes. This section explores the meaning of definition itself, its components, and the various types of definitions categorized by their primary purpose.
After completing this section, you will be able to:
Activity # 1:
How would you define the term "definition" itself?
In logic, definitions primarily aim to explicate word meanings. A definition is a group of words that assigns a meaning to another word or group of words. Every definition consists of two parts:
Example: In the definition:
‘Tiger’ means a large, striped, ferocious feline indigenous to the jungles of India and Asia.
• The definiendum is "Tiger".
• The definiens is "a large, striped, ferocious feline indigenous to the jungles of India and Asia."
It's crucial to understand that the definiens is *not* the meaning itself, but rather the words used to *symbolize* the same meaning as the definiendum. By understanding the meaning symbolized by the definiens (which is assumed to be clearer or more familiar), we come to understand the meaning symbolized by the definiendum. This is how a definition "assigns" meaning.
Activity # 2:
What are some practical purposes for defining words?
Definitions serve various functions. Based on their primary purpose, we can classify definitions into five main types:
Let's examine each type in detail.
A stipulative definition assigns a meaning to a word for the first time. This can involve coining a completely new word or giving a new, specific meaning to an existing word. The primary purpose is often to introduce a convenient shorthand for a more complex expression or concept, especially when dealing with new phenomena, inventions, or classifications.
Example: When tigers and lions were crossbred, the resulting offspring needed names. Instead of using cumbersome descriptions ("offspring of a male tiger and a female lion"), the terms "tigon" and "liger" were stipulated. "Tigon" was stipulated to mean the offspring of a male tiger and a female lion, and "liger" the offspring of a male lion and a female tiger. These definitions introduced new terms for new entities.
Stipulative definitions are also used for creating secret codes (e.g., military code names like "Operation Desert Storm") or specialized terminology within specific fields.
Key characteristics of stipulative definitions:
Stipulative definitions can be misused in disputes if someone assigns a peculiar meaning to a word and assumes others share it. As new concepts and creations emerge, the need for stipulative definitions continues.
A lexical definition reports the meaning(s) a word *already has* within a language community. Its purpose is to inform someone about the established usage of a term. Dictionary definitions are prime examples.
Unlike stipulative definitions, lexical definitions *can* be true or false. A lexical definition is true if it accurately reflects how the word is commonly used; it is false if it does not.
Because words often have multiple established meanings (ambiguity), a key purpose of lexical definitions is to distinguish these various meanings, helping users avoid confusion and use the word correctly.
As noted earlier, ambiguity occurs when a word or phrase has multiple distinct meanings in context (e.g., "light," "bank," "proper"). Lexical definitions address this by listing and clarifying the different senses a word carries.
By consulting lexical definitions, individuals can better understand potential ambiguities, avoid using words ambiguously themselves, and detect ambiguity in others' communication. The most problematic ambiguities often involve subtle shades of meaning rather than drastically different ones. For instance, "nice" can imply various qualities (pleasant, fastidious, precise, etc.). A good lexical definition differentiates these nuances, preventing unintentional conflation.
The purpose of a précising definition is to reduce the vagueness of a word. Vague words lack sharp boundaries of application (e.g., "fresh," "rich," "poor," "tall"). A précising definition draws a specific line to clarify application in a particular context, making the term more precise for a specific purpose (often legal, scientific, or policy-related).
Example: To implement legislation aiding the "poor," a precise definition is needed. A précising definition might state: "'Poor' for the purpose of this statute means having an annual household income below $25,000 and a net worth less than $50,000." This specifies exactly who qualifies.
Words taken from ordinary language and used in specialized fields like science, medicine, or law often require précising definitions (e.g., "force," "acid," "contract," "death"). These definitions clarify meaning within that specific domain.
Legal contexts often rely on précising definitions. A court case might hinge on whether a bicycle counts as a "vehicle" under traffic laws, requiring the court to offer a précising definition for that specific legal context.
Similarly, medical ethics and law required a précising definition for the "moment of death" to facilitate organ transplantation. Issues arose regarding whether death occurs when the heart stops, breathing ceases, or another criterion is met. Courts and medical bodies often adopt definitions based on brain function (e.g., irreversible cessation of all brain activity) as a précising definition for legal and medical purposes. This clarifies the vague concept of "death" in a critical context.
A précising definition takes an existing, often vague, term and makes its boundaries clear for a specific application.
A theoretical definition assigns meaning to a term by connecting it to a broader theoretical framework. It suggests a particular way of understanding the entities denoted by the term, often implying deductive consequences, suggesting avenues for further investigation, and fitting the term into a larger system of concepts.
Example: In physics, the kinetic theory defines heat as follows: "'Heat' means the energy associated with the random motion of the molecules of a substance." This definition doesn't just assign meaning; it embeds "heat" within a specific scientific theory. This theoretical understanding suggests consequences (e.g., faster molecular motion correlates with higher temperature) and motivates further experimental research relating molecular motion to phenomena like radiation and pressure.
Theoretical definitions are common not only in science but also in philosophy. Terms like "substance," "form," "cause," "mind," "good," and "God" often receive theoretical definitions specific to a particular philosophical system. For instance, Leibniz defined "substance" in terms of "monads," grounding his metaphysics, while Mill defined "good" as promoting the greatest happiness for the greatest number, underpinning his utilitarian ethics.
Strictly speaking, theoretical definitions are neither true nor false. They function as proposals for understanding a concept within a specific theory. Their value lies in their fruitfulness—the coherence, explanatory power, deductive consequences, and experimental outcomes they generate within that theoretical framework.
The purpose of a persuasive definition is to influence attitudes by assigning an emotionally charged or value-laden meaning to a term, while presenting it as the term's correct or standard meaning. Persuasive definitions blend stipulative, lexical, and sometimes theoretical elements with a rhetorical goal: to elicit approval or disapproval for the definiendum's subject matter.
Examples:
“Abortion” means the ruthless murdering of innocent human beings.
(Negative attitude)
“Abortion” means a safe and established surgical procedure whereby a woman is relieved of an unwanted burden.
(Positive/Neutral attitude)
More Examples:
“Taxation” means the procedure by means of which our commonwealth is preserved and sustained.
(Positive attitude)
“Taxation” means the procedure used by bureaucrats to rip off the people who elected them.
(Negative attitude)
While persuasive definitions might be evaluated for factual accuracy (like lexical definitions), their primary aim is persuasion. Their effectiveness lies in shaping the audience's attitude towards the subject. They are common tools in political rhetoric and opinion pieces but should be recognized for their persuasive intent rather than accepted as purely objective definitions.
The previous section surveyed the various types of definitions based on their purposes. This section explores the *techniques* used to construct these definitions. These techniques generally fall into two categories, corresponding to the two kinds of meaning discussed earlier: extensional (denotative) techniques and intensional (connotative) techniques.
After completing this section, you will be able to:
Activity # 1:
What does it mean to define a term extensionally?
An extensional definition assigns meaning to a term by indicating the members (the extension) of the class the term denotes. There are three main ways to do this:
Demonstrative (or Ostensive) definitions define a term by pointing to objects it denotes. This is perhaps the most basic form of definition, requiring only an understanding of the act of pointing. These definitions can be partial (pointing to some examples) or complete (pointing to all members, if feasible).
Examples:
“Chair” means *this* and *this* and *this* (while pointing to several chairs).
“Washington Monument” means *that* (while pointing to the monument).
Ostensive definitions are essential when teaching a language from scratch but are limited. The object must be present to be pointed at (e.g., you can't ostensively define "sun" at night). Furthermore, like all extensional definitions, they point to examples but don't fully capture the defining attributes (intension).
Enumerative definitions assign meaning by naming individual members of the class denoted by the term. Like demonstrative definitions, they can be partial or complete.
Examples:
“Actor” means a person such as Abebe Balcha, Samson Taddesse, or Mahder Assefa. (Partial)
“Baltic states” means Estonia, Latvia, and Lithuania. (Complete)
Complete enumerative definitions are often more informative, but fully listing all members is only practical for classes with a small, finite number of members.
Definition by subclass assigns meaning by naming specific subclasses of the class denoted by the term. This technique can also be partial or complete.
Examples:
“Tree” means an oak, pine, elm, spruce, maple, etc. (Partial)
“Fictional work” means a poem, a play, a novel, or a short story. (Arguably complete for major types)
“Mammal” means a primate, rodent, canine, feline, cetacean, etc. (Partial)
Complete definitions by subclass offer greater clarity but are often impractical, as many classes contain numerous subclasses.
Extensional techniques are primarily used for creating lexical and stipulative definitions. Dictionaries often employ enumeration or definition by subclass (sometimes pictures, akin to demonstrative definitions) to illustrate actual word usage. Stipulative definitions can use pointing, enumeration, or subclass naming to assign meanings to new terms or groups.
Extensional definitions are less suitable for précising definitions. Précising definitions aim to clarify vague *intensional* meaning. Attempting to resolve intensional vagueness by exhaustively listing the *extension* is problematic because vagueness often implies uncertainty about the extension's exact boundaries. It essentially tries (and fails) to have extension determine intension.
While extensional definitions can *suggest* a term's meaning, they cannot precisely determine its essential attributes (intension). Therefore, adequate lexical definitions usually require intensional techniques alongside or instead of purely extensional ones.
Activity # 2:
What does it mean to define a term intensionally?
An intensional definition assigns meaning by indicating the qualities or attributes (the intension) that the term connotes. Four primary strategies achieve this:
A synonymous definition defines a term using a single word (a synonym) that shares the same intension (connotes the same attributes).
Examples:
“Physician” means doctor.
“Observe” means see.
“Terminate” means end.
This technique offers conciseness when a true synonym exists. However, perfect synonyms are rare; many words possess subtle nuances not captured by any single alternative (e.g., "wisdom" isn't perfectly synonymous with "knowledge" or "understanding").
An etymological definition assigns meaning by revealing a word's ancestry and historical development, tracing its origins in its own or other languages.
Example:
The English word “license” derives from the Latin verb *licere*, meaning "to be permitted."
The word "philosophy" derives from the Greek *philos* (love) and *sophia* (wisdom).
Etymological definitions are valuable for two main reasons:
An operational definition assigns meaning to a term by specifying a measurement procedure or experimental operation that determines whether the term applies in a given situation. Operational definitions define concepts in terms of observable, repeatable operations.
Examples:
A solution is “acidic” if and only if litmus paper turns red when dipped into it.
One substance is "harder" than another if and only if the first substance scratches the second when the two are rubbed together.
These definitions prescribe specific operations. A definition lacking such a procedure is not operational, even if scientifically useful (e.g., defining "acid" by pH level is not operational unless the method for measuring pH is specified as the operation).
Operational definitions are particularly useful in scientific contexts where precise, empirical criteria for applying terms are needed. They aim to eliminate ambiguity and vagueness by tying meaning to concrete procedures.
However, operational definitions have limitations. They may not capture the full theoretical or conceptual meaning of a term. For example, defining "intelligence" solely by performance on an IQ test (an operational definition) might exclude other important aspects of intelligence not measured by that specific test. They define a term only in the context of the specified operation.
Definition by genus and difference is often considered the most effective intensional technique. It assigns meaning by:
1. Identifying a genus: A larger class to which the term's referents belong.
2. Identifying the specific difference (or differentia): The attribute(s) that distinguish the members of the term's class (the species) from other members of the genus.
In logic, "genus" and "species" refer to relative class inclusion (broader class and narrower subclass), not strictly the biological classifications. For example, 'animal' is the genus for the species 'mammal'; 'mammal' is the genus for the species 'feline'; 'feline' is the genus for the species 'tiger'.
The specific difference isolates the species within the genus. Combining genus and difference yields the definition.
To construct a definition by genus and difference:
Example: Define "ice".
Definition: "Ice" means frozen water.
More examples:
Definition by genus and difference is versatile and widely applicable. It can be used to construct all five types of definitions discussed earlier (stipulative, lexical, précising, theoretical, persuasive), although lexical definitions often incorporate other techniques like etymology as well. Operational definitions, while useful, often cannot provide a complete lexical meaning alone and usually need supplementation.
Among the five types of definitions discussed, lexical definitions (reporting established word usage) are the most common in everyday life and are typically what people mean by "definition." This section outlines established rules or criteria for constructing and evaluating good lexical definitions.
After completing this section, you will be able to:
Since lexical definitions aim to accurately report common word usage, certain criteria help ensure their quality and usefulness. While some rules might apply broadly, these are particularly relevant for lexical definitions. Other definition types (stipulative, précising, etc.) have unique functions that might lead to different criteria.
We will examine eight common rules for evaluating lexical definitions.
Rule 1: A Lexical Definition Should Conform to the Standards of Proper Grammar.
Definitions, like all expressions, should be grammatically correct. Avoid structures where the definiens doesn't match the grammatical form of the definiendum.
Incorrect Examples:
Vacation is *when* you don’t have to go to work or school. (Defines noun with adverbial clause)
Furious means *if* you’re angry at someone. (Defines adjective with conditional clause)
Corrected Examples:
“Vacation” means a period during which activity is suspended from work or school.
“Furious” means exhibiting or marked by extreme anger.
Conventionally, the definiendum is quoted or italicized, though this isn't always strictly followed.
Rule 2: A Lexical Definition Should Convey the Essential Meaning of the Word Being Defined.
A definition is unhelpful if it fails to capture the core attributes that define the term's common usage. For example, defining "human" as simply "featherless biped" misses the essential attributes of reason and sophisticated language use that distinguish humans. A better definition, like "'Human' means the animal possessing the capacity to reason and speak," captures more essential meaning.
Lexical definitions using operational or extensional techniques often need supplementation with intensional methods (especially genus and difference) to convey essential meaning fully. Operational definitions might focus on non-essential aspects tied to the operation, while extensional definitions only suggest, rather than precisely state, the essential attributes. An adequate lexical definition usually requires capturing the term's intension.
Rule 3: A Lexical Definition Should Be Neither Too Broad nor Too Narrow.
Example: Defining "bird" as "any warm-blooded animal having wings" is too broad (includes bats). Defining "bird" as "any warm-blooded, feathered animal that can fly" is too narrow (excludes flightless birds like ostriches).
This rule primarily applies to synonymous definitions (ensure true synonymy) and definitions by genus and difference (ensure the specific difference correctly delimits the species within the genus).
Rule 4: A Lexical Definition Should Avoid Circularity.
A circular definition uses the term being defined (or a close variant) within the definiens, making it uninformative to someone who doesn't already know the meaning.
Examples of Circularity:
“Quiet” means quietude. (Synonymous)
“Silence” means the state of being silent. (Genus & Difference)
“Gambler” means someone who gambles. (Genus & Difference)
Circularity can also occur between pairs of definitions:
“Science” means the activity engaged in by scientists.
“Scientist” means anyone who engages in science.
Operational definitions can also be circular if understanding the operation presupposes understanding the term being defined (e.g., "'Time' means whatever is measured by a clock").
Rule 5: A Lexical Definition Should Not Be Negative When It Can Be Affirmative.
Definitions should explain what a term *is*, not just what it *is not*, whenever possible.
Comparison:
Affirmative: “Concord” means harmony.
Negative: “Concord” means the absence of discord.
The affirmative definition is generally preferred as it is more direct.
However, some terms are intrinsically negative, representing an absence or lack. For these, a negative definition is appropriate and often necessary.
Appropriate Negative Definitions:
“Bald” means lacking hair.
“Darkness” means the absence of light.
“Orphan” means a child without living parents.
Rule 6: A Lexical Definition Should Avoid Figurative, Obscure, Vague, or Ambiguous Language in the Definiens.
The language used to define (definiens) should itself be clear and precise.
The goal is clarity; the definiens should illuminate, not further confuse, the meaning of the definiendum.
Rule 7: A Lexical Definition Should Avoid Affective Terminology.
Affective terminology includes language that primarily aims to express or evoke emotions, or to influence attitudes, rather than objectively convey meaning. This includes sarcastic, facetious, or emotionally loaded language. Lexical definitions should strive for neutrality.
Example (Affective/Biased):
“Communism” means that “brilliant” invention of Karl Marx and other foolish political visionaries in which the national wealth is supposed to be held in common by the people.
This definition injects the definer's negative attitude rather than neutrally reporting the term's meaning.
Rule 8: A Lexical Definition Should Indicate the Context to Which the Definiens Pertains, if Necessary.
For words with multiple meanings depending on the context or field, the definition should specify the relevant context to avoid ambiguity.
Examples (Context Specified):
“Strike” means (in baseball) a pitch at which a batter swings and misses, or which passes through the strike zone without being swung at.
“Strike” means (in bowling) the act of knocking down all the pins with the first ball of a frame.
“Strike” means (in labor relations) a work stoppage undertaken by employees to exert pressure on an employer.
Explicitly stating the context (e.g., "in baseball") is best, but sometimes the phrasing of the definiens implicitly indicates the context.
Language is fundamental to logic. Since logic studies arguments, and arguments are constructed and conveyed through language, understanding language is essential. Clarifying terms and statements is a core task in logic and philosophy. Careful attention to language is necessary for interpreting, analyzing, and evaluating arguments effectively, as many logical errors arise from imprecise or misunderstood language.
Meanings and definitions are crucial for clear communication and rigorous argument evaluation. Before assessing an argument's validity or soundness, understanding the meanings of its constituent words and statements is necessary.
Language serves various functions, but logic primarily focuses on conveying information (cognitive meaning) and expressing/evoking feelings (emotive meaning). Emotive language often carries implicit value claims. For logical analysis, it's vital to separate cognitive content (including value claims) from emotive coloring.
Cognitive meaning can be compromised by vagueness (imprecise boundaries) and ambiguity (multiple distinct meanings). These linguistic issues can lead to verbal disputes, which center on language meaning, as opposed to factual disputes, which concern disagreements about facts. Recognizing the type of dispute is key to resolving it.
Terms possess both intensional meaning (connotation: attributes) and extensional meaning (denotation: members of the class). Intension generally determines extension. Even terms with empty extension have intension.
Definitions explicate meaning and consist of a definiendum (term defined) and a definiens (defining words). Definitions serve various purposes, leading to types like stipulative (assigning new meaning), lexical (reporting existing meaning), précising (reducing vagueness), theoretical (connecting to a theory), and persuasive (influencing attitude). These are constructed using extensional techniques (demonstrative, enumerative, subclass) or intensional techniques (synonymous, etymological, operational, genus/difference). Lexical definitions, being common and crucial, should adhere to specific rules ensuring clarity, accuracy, and neutrality.
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