To make weak definitions stronger and bad ones better and to set a high standard for all define, the following rules should be respected else the definitions will commit errors. (Fallacies)
- The definition should be adequate. It must be exact. I.e. not too wide, not too broad not too narrow.
- Examples of too narrow and inadequate definitions are;
- Fragrance means any odor.
- Humanity is rationalty.
- Examination is testing ones knowledge.
- Examples of too broad, too wide definitions are;
- The moon is a star that shines.
- A hen is a bird
Any definition which goes against this rule commits the fallacy of incongruous definition.
- The definition must be précised and clear: i.e. it should not be ambiguous, obscure, and superfluous nor be expressed in figurative language e.g.
- Man as a featherless biped
- Singing is a romantic display of musical instruments
- A torch is the eye of a hunter.
All these definitions are figurate, metaphorical, ambiguous, and not clear or not précised. Hence, committing the fallacy of obscure definition.
- A definition should not be circular: i.e. it must avoid synonyms and antonyms. A circular definition goes round and round without making an advance. Examples of circular definitions are.
- To fish means to use a hook to catch a fish.
- A teacher is a person who teaches.
- A philosopher is a person who espouses philosophy.
These definitions commit the fallacy of circular definition. Avoid using the same term in definition.
- A definition should be per genus ET differentia: By this the essential attributes of the species are stated. E.g. man can be defined as a rational animal. This definition is boy genus and differentia. The error that such definitions commit is called extraneous fallacy.
- A definitions should not be negative where it can be affirmative: A definition is supposed to explain what a term means and not what it does not mean. Examples of negative/ fallacious definitions are;
- Love is the tendency not to hate others.
- An ape is a non-intelligent animal.
- A clair is not a bed.
These definitions would have been in the affirmative but they are in the negative. Hence, committing the fallacy of negative definitions. Avoid using negative terms in defining.
