Definitions and Defining Techniques
A definition refers to a group of words that is used to give meaning to other words. This immediately implies that a definition will have two parts. The first part is the very word to be defined, also called the definiendum. The second part is the group of words to be used for defining, also known as the definiens.
So, if we define a 'telephone" as "an electronic device that enables speech communication between at least two people," the definiendum in the definition will be 'telephone' while the definiens will be 'an electronic device that enables speech communication between at least two people.' The definiens is then the group of words that signals or directs us to what the meaning of that word entails.
Purposes of Definitions
There are five purposes of definitions that translate into the five types of definitions that are available for understanding the meanings of words. These five purposes are:
- To increase vocabulary: Definition is needed in this case to increase one's reservoir of meaningful words. When I define in this case, I have the intention of understanding a particular word that is new to me.
- To remove ambiguity: Ambiguity applies to words that possess two or more different meanings. On occasions, such words become problematic because you are really not which of the senses of the word is intended. Equivocation can become a dangerous linguistic form of deceit in such cases. Ambiguity also raises the problem of verbal disputes (as opposed to factual disputes). A verbal dispute is a prolonged disagreement on the meaning of a word. For instance:
Muhammad: Shola is guilty of stealing the phone. He confessed to me yesterday that he did it.
Chinedu: How can you say that? Shola has not even been accused by the court. No one is guilty until the court says so.
Here, the dispute turns on the meaning of 'guilty'. While Muhammad took the word in its moral sense, Chinedu insisted on its legal implication. A definition is therefore, required to clarify the ambiguity involved.
- To reduce vagueness: A vague word, unlike the ambiguous word, has a wide range of possible meanings which can only be limited by defining the context for using the word. Being 'drunk', for instance, is vague. It could apply to taking one, two, three bottles, a carton or two or three or more of beer/wine/other alcoholic drink. Only a definition can stipulate the sense of 'drunk' one is working with.
- To give theoretical explanation: In this case, a definition provides a theoretical or scientific explanation of a term in scientific usage.
- To influence other people's attitudes: Finally, a definition also serves a persuasive purpose in the sense that such a definition affects the way another person relates with the word that is defined. Thus, the reason why a person defines in this context is not to explain, remove ambiguity or reduce vagueness; rather, the purpose is to elicit an emotional reaction in the other person.
Types of Definitions
The five purposes of definitions outlined above allow logicians to fabricate a pragmatic approach to the utility of definitions. This pragmatism takes the middle course between philosophers who claim that a definition does not really provide any information about the definiendum, and those who claim that definitions provide urgent clarifications which enable us to achieve deeper truth on the satu bend meaning of language.
For logicians, jabbetter approach is to outline the 1979 of definitions available to us, and their relevance in helping us deal with the complexities involved in language use.
1. Stipulative Definition
This is word that the definition given to a new is just being introduced into the language. Such new words are called neologies. And the person introducing them is at complete liberty to give them any definition s/he wants. Stipulative definition may also involve giving a new ga meaning to an old word.
New words are usually required for new development not already captured in the existing vocabulary. It may also be required when there is a need to set up secret codes of communication or for naming purposes in the sciences. For instance, 'the offspring of a male tiger and a female lion' could be called a 'tigon' (or any other arbitrary formulation). The 'offspring of a male lion and a female tiger' can be called a 'liger'.
It should be noted that, apart from being an arbitrary creation, a stipulative definition does not tell us any new thing about the definiendum.
2. Lexical Definition
This type of definition does not arise from an arbitrary creation of neologies. Rather, it is used to report an established conventional usage of a word. Such an established usage of any word is found in dictionaries. Lexical definitions, unlike the stipulative, can be either true or false because we can have a correct or incorrect interpretation of an actual use of a particular word. If someone defines a 'bachelor' as a married male, that would constitute a false lexical definition because it does not report the conventional use of that word.
Further, lexical definitions allow for the elimination of vague and ambiguous words. A good lexical definition will outline the various senses and meaning of vague and ambiguous words.
3. Precising Definition
This definition applies solely to vague words, and it enables us to specify a particular context or purpose which unravels the vague word beyond what the lexical definition is capable of doing.
Words like 'love,' 'most,' 'early,' 'rich,' 'soon,' 'fresh,' 'excessive,' 'normal, 'moderate,' 'furniture,' 'peace,' 'hot,' 'beauty/ beautiful,' 'clear,' 'definite,' 'bad,' 'critical,' etc. are vague words that require operational usage to fix a specific context that clarifies them. Thus, we can say: 'In this legislation, "poor" will mean having an annual income of less than 50,000. That is a precising definition because it has fixed the meaning of 'poor' within a particular piece of legislation.
In another context, a court could fix the meaning of 'death' by a precising definition of what constitutes the cessation of life: when the heart stops beating; when a person stops breathing; when the brain stops working; when rigor mortis sets in; and so on. Another example: 'In the context of this relationship, "love" means 'taking me to the cinema once in a month.' This fixation of exact meaning is not stipulative because it still operates within the context of lexical definitions.
4. Theoretical Definition
This type of definition is common in philosophy and the sciences. It theoretically formulates an adequate characterisation of an object to which the definition applies. Or: a theoretical definition gives a conceptual or scientific clarification of the entity or object that the term to be defined denotes.
Words like 'heat,' 'force,' 'light,' 'element,' 'weight,' or philosophical terms like 'substance,' 'equality,' 'virtue,' 'cause,' 'idea,' 'good,' and 'mind', require theoretical definitions. Often, these definitions require a background theory that grounds the meaning of the entity or concept to be defined. Thus, 'light' may be defined within the context of Newtonian or Einstein's relativity theory in mind, while 'substance' may be defined in the context of an Aristotelian or Leibnitzian philosophy.
An example of a theoretical definition is:
- 'heat' means the energy association with the random motion of the molecules of a substance;
- 'weight' means a measurement of gravitational force acting on an object.
5. Persuasive Definition
This definition is proposed as a means of influencing or evoking a change of attitude towards what is denoted by the definiendum. In other words, when a persuasive definition is given, it is meant to engender a favourable or unfavourable emotion to the term being defined.
If I say: "Abortion means the cruel and insensitive murder of an unborn person," that definition is meant to provoke an unfavourable reaction in the hearer. On the other hand, a favourable definition could be: "Abortion means a safe surgical operation that removes an unwanted mass of bloody tissue from a woman."
6. Ostensive Definition
This definition is mainly used when a particular term or word is very difficult to define verbally or when a child is getting introduced to a word for the first time. Ostensive definition is primarily achieved through pointing at the object that illuminates the word to be defined. For instance, "That is colour red," gives an ostensive definition by pointing at a red apple or a red car or a red house.
Rules for Lexical Definition
There are eight definite rules that fix the acceptable boundary of all lexical definitions. This means that these rules enable us to appraise the adequacy of any proposed lexical definition. These rules apply mostly to lexical definitions because they are the most common of all the definitions that we make use of when we ask for the meaning of any word.
The criteria for evaluating these definitions include the following:
• Rule 1:
A lexical definition must give the essential meaning of the word to be defined. This implies that such a definition must point at those significant attributes that differentiates the word being defined from other words. For example: If 'human' is defined as 'a featherless biped,' that definition will not distinguish a human from, say, a chicken whose feathers have been plucked. A better definition that recognises the essence of man would be: 'human' means an animal that has the capacity to reason.
• Rule 2:
A lexical definition must be grammatically correct. Compare these two definitions: (a) 'Vacation is when you don't have to go to work or attend school' and (b) 'Vacation' means a period of time during which there is a suspension of any activity at work or in school. The second definition is grammatically correct while the first is not.
• Rule 3:
A lexical definition must not be circular. A definition is circular if it imports the definiendum into the definiens. Since the purpose of a lexical definition is to provide the explanation of a particular word (the definiendum), then such a word must not appear in the set of words that is meant to provide such an explanation (definiens). For instance: 'Silent' means a state of being silent; 'Science' means the activity engaged in by scientists; 'Time' is whatever is measured by a clock, etc.
• Rule 4:
A lexical definition must not be too broad or too narrow. In a broad definition, the definiens explains too much, while in a narrow one, the definiens fails to achieve an adequate explanation. If a 'bird' is defined as 'a warm- blooded, feathered animal that can fly,' that would be a narrow definition that will exclude ostriches which are birds but cannot fly. However, if a 'bird' is defined as a 'warm- blooded, feathered animal with wings, that would be too broad and will include, say, bats which are technically not birds.
• Rule 5:
A lexical definition must not be negative where it can be affirmative. Consider two examples: 'Concord' means the absence of disagreement; and 'Concord' means peaceful coexistence. Of the two, the second example is better than the first because a definition is supposed to give the meaning of a word and not what it does not mean. However, this rule is tempered by certain words which are intrinsically negative. 'Darkness', for instance, automatically means the 'absence of light.'
• Rule 6:
A lexical definition must not be expressed in ambiguous, obscure or figurative language. The following definitions will fail this rule:
- 'Painting' is silent poetry (figurative);
- 'Network' means anything reticulated, or decussated, at equal distances, with interstices between the intersections (obscure).
• Rule 7:
A lexical definition must avoid emotional terminologies. Emotive words attempt to influence the attitude towards a particular definition. Such words must be rejected in a lexical definition. The following definition violates rule 7: 'Capitalism' is a cruel ideology that makes it possible for the rich to continually exploit the poor.
• Rule 8:
A lexical definition must indicate the context to which a word applies. This rule applies to certain words which require a specific context to be properly understood. A word like 'deuce' is meaningful only in a tennis game. A lexical definition therefore, specifies the context that makes a word meaningful: 'Strike' means (in fishing) a pull on a line that is made when a fish takes the bait.