Глава VIII. Об определении

A definition is a short speech expressing the nature of the subject, i.e. speech denoting this nature in a few words. For example, man is a rational animal, mortal, capable of understanding and comprehension. Many people have composed broad words about human nature, i.e. lengthy and pompous, but since they are not short, they are not definitions. On the other hand, there are also short words, such as sayings (αποφθεγματα), but since they do not express the nature of a thing, they are not definitions. And the name, although it often expresses the nature of the subject matter, is not a definition, for the name is one word (λεξις), the definition is speech (λογος), and speech is composed of at least two different words. [A term is a name explained, a name is a term in a compressed form]. The definition is made up of the genus and the generators (συστατικον), i.e. significant (ουσιωδων) differences. This can be seen in the definition of an animal: an animal is an animate substance with the ability to perceive. In this definition, substance is a genus, and animation and the faculty of perception are formative differences. Composed (definition) of matter and form. For example, a statue is something that is made of copper and depicts a person. So, copper is matter and “depicts a person” - the form of a statue. In this case, matter corresponds to the genus, while form corresponds to the difference. A definition is also drawn up from the subject being studied and the purpose. For example, medicine is an art that has human bodies as its subject, and sets health as its goal. Here the subject of medicine is human bodies, and the goal is its health. The description is made up of insignificant features, i.e. properties and accidents. For example; Man is an animal that can laugh, has a straight gait and flat nails. All these are insignificant signs. Therefore, the description is called (in Greek) (υπογραφη), since it gives, as it were, a shadow of an object and expresses not the essential being, but what accompanies it. A descriptive definition is a mixture of essential and non-essential features of the subject. For example, a person is a rational animal with a straight gait and flat nails. The definition (in Greek) is called (ορισμος) from the metaphor of land boundaries. Just as a boundary separates the property of each person from the property of another, so a definition separates the nature of each thing from the nature of another. The advantage of a definition is that it is neither sparse nor full of words. Its disadvantage is the scarcity or excess of words. A perfect definition will be one that allows handling of the defined object, an imperfect definition will be one that does not allow handling. A definition that is meager in words does not allow for conversion. When a definition abounds in words, it is already a thing being defined; when it is sparse in words, it abounds in objects. [Thus we can say that nature has invented an amazing device: abundant poverty and wealth that hides poverty]. For example, a perfect definition of a person would be the following: a person is a rational, mortal animal. This definition allows for conversion, for every rational, mortal animal is a human being, and every human being is a rational, mortal animal. If one word is omitted from this definition, then it will be broader than the subject being defined - for example, a person is a rational animal. There is one word missing from this definition because I did not add: mortal. Therefore, it abounds in objects, for not only man is a rational animal, but also an angel, and therefore it does not allow conversion. If I say: man is a rational, mortal and learned animal, then this definition also does not allow for conversion, for it is replete with words, as it is said: learned. Therefore, it is already a defined object, for it does not define every person, but only scientists. Indeed, every rational, mortal and learned animal is a man, but not every human is a rational, mortal and learned animal, for not every man is a scientist. So, those definitions that allow handling of the defined object will be perfect. But since property also allows for circulation with the object to which it belongs - for if a certain being is a man, then it is capable of laughing, and if it is capable of laughing, then it is also a man - therefore we must, adding to the definition given earlier, say that perfect definitions are those that are made up of genus and formative differences, in which no more and no less is said than should be, and which allow manipulation with the defined. Likewise (perfect determinations) will be those which are composed of object and purpose, and also of matter and form. Sometimes (perfect) are definitions that consist of one object - namely, when the object is not subject to another art, such as glass - glass art - and from one goal, when this goal cannot be the goal of other arts, as for example, this is the case in relation to shipbuilding. From all this it should be concluded that the perfection of the definition lies in its ability to be addressed. The name "definition" (ορισμος) differs from the name "term" (ορος) in that the former is narrower and the latter is wider. In fact, the “term” (ορος) denotes both the land boundary and the decision, for example, when we say “ωρισεν βασιλευς” (the king decided). In the same way, it means what the premise is decomposed into, as we, with God’s help, will find out later. It also denotes a definition; a definition denotes only a short speech expressing the nature of the subject thing. It should be noted that the definition is only possible in relation to the substance and its types. As for the individual and accidents, it is impossible to define them, but only to describe them, since the definition is made up of the genus and formative differences, while the description is made up of unimportant characteristics. You might be interested in: