On Interpretation

Aristotle's De Interpretatione (the Latin title by which it is usually known) or On Interpretation (Greek Περὶ Ἑρμηνείας or Peri Hermeneias) is one of the earliest surviving philosophical works in the Western tradition to deal with the relationship between language and logic in a comprehensive, explicit, and formal way.

The work begins by analyzing simple categoric propositions, and draws a series of basic conclusions on the routine issues of classifying and defining basic linguistic forms, such as simple terms and propositions, nouns and verbs, negation, the quantity of simple propositions (primitive roots of the quantifiers in modern symbolic logic), investigations on the excluded middle (what to Aristotle isn't applicable to future tense propositions — the Problem of future contingents), and on modal propositions.

The first five chapters deal with the terms that form propositions. Chapters 6 and 7 deal with the relationship between affirmative, negative, universal and particular propositions. These relationships are the basis of the well-known Square of opposition. The distinction between universal and particular propositions is the basis of modern quantification theory. The last three chapters deal with modalities. Chapter 9 is famous for the discussion of the sea-battle. (If it is true that there will be a sea-battle tomorrow, then it is true today that there will be a sea-battle. Thus a sea-battle is apparently unavoidable, and thus necessary).

De Interpretatione is (the second) part of the Organon, Aristotle's collected works on logic.

Contents

Chapter 1. Aristotle defines words as symbols of 'affections of the soul' or mental experiences. Spoken and written symbols differ between languages, but the mental experiences are the same for all (so that the English word 'cat' and the French word 'chat' are different symbols, but the mental experience they stand for - the concept of a cat - is the same for English speakers and French speakers). Nouns and verbs on their own do not involve truth or falsity.

Chapter 2. A noun signifies the subject by convention, but without reference to time (i.e. 'Caesar' signifies the same now, two thousand years after his death, as it did in Roman times).

Chapter 3. A verb carries with it the notion of time. 'He was healthy' and 'he will be healthy' are tenses of a verb. An untensed verb indicates the present, the tenses of a verb indicate times outside the present.

Chapter 4. The sentence is an expression whose parts have meaning. The word 'man' signifies something, but is not a sentence. Only when words are added to it do we have affirmation and negation.

Chapter 5. Every simple proposition contains a verb. A simple proposition indicates a single fact, and the conjunction of its parts gives a unity. A complex proposition is several propositions compounded together.

Chapter 6. An affirmation is an assertion of something of something, a denial an assertion denying something of something. (For example, 'a man is an animal' asserts 'animal' of 'man'. 'A stone is not an animal' denies 'animal' of stone').

Chapter 7. Terms. Some terms are universal. A universal term is capable of being asserted of several subjects (for example 'moon' - even though the Earth has one moon, it may have had more, and the noun 'moon' could have been said of them in exactly the same sense). Other terms are individual. An individual or singular term ('Plato') is not predicated (in the same) sense of more than one individual.

A universal affirmative proposition such as 'every man is white', and a universal negative proposition having the same subject and predicate such as 'no man is white' are called contrary. A universal affirmative proposition (every man is white) and the non-universal denial of that proposition in a way (some man is not white) are called contradictories. Of contradictories, one must be true, the other false. Contraries cannot both be true, although they can both be false, and hence their contradictories are both true (for example, both 'every man is honest' and 'no man is honest' are false. But their contradictories 'some men are not honest' and 'some man are honest' are both true.

Chapter 8. An affirmation is single, if it expresses a single fact. For example 'every man is white'. However, if a word has two meanings, for example if the word 'garment' meant 'a man and a horse', then 'garment is white' would not be a single affirmation, for it would mean 'a man and a horse are white', which is equivalent to the two simple propositions 'a man is white and a horse is white'.

Chapter 9. Of contradictory propositions about the past, one must be true, the other false. But when the subject is individual, and the proposition is future, this is not the case. For if so, nothing takes place by chance. For either the future proposition such as 'a sea battle will take place' corresponds with future reality, or its negation does, in which case the sea battle will take place with necessity, or not take place with necessity. But in reality, such an event might just as easily not happen as happen; the meaning of the word 'by chance' with regard to future events is that reality is so constituted that it may issue in either of two opposite possibilities. This is known as the problem of future contingents.

Chapter 10. Aristotle enumerates the affirmations and denials that can be assigned when 'indefinite' terms such as 'unjust' are included. He makes a distinction that was to become important later, between the use of the verb 'is' as a mere copula or 'third element', as in the sentence 'a man is wise', and as a predicate signifying existence, as in 'a man is [i.e. exists]'.

Concise remarks on De interpretatione as being at the origin of the logical square and of modal logic

The logical square, also called square of opposition or square of Apuleius has its origin in the four marked sentences to be employed in syllogistic reasoning: Every man is white, the universal affirmative and its negation Not every man is white (or Some men are not white), the particular negative on the one hand, Some men are white, the particular affirmative and its negation No man is white, the universal negative on the other. Robert Blanché published with Vrin his Structures intellectuelles in 1966 and since then many scholars think that the logical square representing four values should be replaced by the logical hexagon which by representing six values is a more potent figure because it has the power to explain more things about logic and natural language. The study of the four propositions constituting the square is found in Chapter 7 and its appendix Chapter 8. Most important also is the immediately following Chapter 9 dealing with the problem of future contingents. This chapter and the subsequent ones are at the origin of modal logic. Perhaps Blanché's hexagon is particularly useful in the domain of modal logic in so far as it explains clearly the nature and importance of the bilateral possible. The notion of bilateral possible is crucially important to understand both logic and natural language when applied to modal values.

See also

• Hermeneutics
• Interpretation
• Semeiotic
• Semiosis
• Semiotics
• Sign
• Sign relation

External links

• Text of On Interpretation, as translated by E. M. Edghill
• Aristotle's De Interpretatione: Semantics and Philosophy of Language with an extensive bibliography of recent studies
• The Master Argument: The Sea Battle in De Intepretatione 9, Diodorus Cronus, Philo the Dialectician with a bibliography on Diodorus and the problem of future contingents
• Sea Battle Hub, a tutorial introduction to the discussion of the truth status of future events from De Interpretatione 9.
• Audiobook of On Interpretation, as translated by Octavius Owen (Public Domain).
• Jules Vuillemin, "Le chapitre IX du De Interpretatione d'Aristote - Vers une réhabilitation de l'opinion comme connaissance probable des choses contingentes, in Philosophiques, vol. X, n°1, April 1983 Template:Fr icon