Organon

The Organon is the name given by Aristotle's followers, the Peripatetics, to the standard collection of six of his works on logic. The works are Categories, Prior Analytics, De Interpretatione, Posterior Analytics, Sophistical Refutations, and Topics.

Constitution of the texts

The order of the works is not chronological (which is now hard to determine) but was deliberately chosen by the Peripatetics to constitute a well-structured system; indeed some parts of them seem to be a scheme of a lecture on logic. The arranging of the works was conducted by Andronicus of Rhodes around 40 BC.¹ Aristotle's Metaphysics has many points of intellectual overlap with the works making up the Organon but is not traditionally considered part of it; additionally there are works on logic attributed, with varying degrees of plausibility, to Aristotle that were not known to the Peripatetics.

• The Categories (Latin: Categoriae) introduces Aristotle's 10-fold classification of that which exists. These categories consist of substance, quantity, quality, relation, place, time, situation, condition, action, and passion.
• On Interpretation (Latin:De Interpretatione) introduces Aristotle's conceptions of proposition and judgement, and treats contrarieties between them. It contains Aristotle's principal contribution to philosophy of language. It also discusses the Problem of the futures contingents.
• The Prior Analytics (Latin: Analytica Priora) introduces his syllogistic method, which is discussed in the article on term logic, argues for its correctness, and discusses inductive inference.
• The Posterior Analytics (Latin: Analytica Posteriora) discusses correct reasoning in general.
• The Topics (Latin: Topica) treats issues in constructing valid arguments, and inference that is probable, rather than certain. It is in this treatise that Aristotle mentions the idea of the Predicables, which was later developed by Porphyry and the scholastic logicians.
• Sophistical Refutations (Latin: De Sophisticis Elenchis) gives a treatment of logical fallacies, and provides a key link to Aristotle's work on rhetoric.

Influence

Aristotle's works the Categories and On Interpretation are the only significant works of Aristotle that were never lost in Western Europe; his other books were ignored in Western Europe (although preserved in the Greek-speaking lands of the Roman Empire) from his death, until translated to Latin in the 12th century. The Organon was used in the school founded by Aristotle at the Lyceum, and some parts of the works seem to be a scheme of a lecture on logic. So much so that after Aristotle's death, his publishers (Andronicus of Rhodes in 50 BC, for example) collected these works. In these works are the first ontological category theory (relevant in some branches of intensional logic), the first development of formal logic, the first known serious scientific inquisitions on the theory of (formal and informal) reasoning, the foundations of modal logic, and some antecedents of methodology of sciences. The Organon was not always popular during the Hellenistic era. Stoic logic was predominant, particularly the work of Chrysippus (none of which has survived). In the 8th century the Scholastics, in non-Arab Europe, studied and promoted the study of logic based on the Organon. One of the greatest Scholastics was Dominican monk Albertus Magnus (1206–1280), the teacher of Thomas Aquinas (1226–1274). The books of Aristotle were available in the Arab Empire and were studied by Islamic and Jewish scholars, including Rabbi Moses Maimonides (1135–1204) and Muslim Judge Ibn Rushd (1126 - 1198); both lived in Cordoba, Spain. Cordoba had 70 libraries, one of them with over 40,000 volumes; the two largest libraries in non-Arab Europe each had only 2,000 volumes. Thomas Aquinas used the writings and comments of Aristotle ("the philosopher"), Albert, Maimonides ("the Rabbi") and Ibn Rushd ("the commentator") and many others. In the Enlightenment there was a revival of interest in logic as the basis of rational enquiry, and a number of texts, most successfully the Port-Royal Logic, polished Aristotelian term logic for pedagogy. During this period, while the logic certainly was based on that of Aristotle, Aristotle's writings themselves were less often the basis of study. There was a tendency in this period to regard the logical systems of the day to be complete, which in turn no doubt stifled innovation in this area. However Francis Bacon published his Novum Organum ("The New Organon") as a scathing attack in 1620 ^[1]. Immanuel Kant thought that there was nothing else to invent after the work of Aristotle, and a famous logic historian called Karl von Prantl claimed that any logician who said anything new about logic was "confused, stupid or perverse." These examples illustrate the force of influence which Aristotle's works on logic had. Indeed, he had already become known by the Scholastics (medieval Christian scholars) as "The Philosopher", in large part due to the influence he had upon Aquinas. The dogmatism created by the Scholastics in favor of Aristotle did not disappear until the early modern period. Since the historical discoveries and logic innovations of the 19th century, particularly the discovery of Indian logic, George Boole's algebraic logic and the formulation of predicate logic, Aristotelian logic no longer has such prestige and is mainly studied out of historical interest. There is, however, a mostly pedagogical interest in term logic deriving from its close structure to the actual forms of reasoning encountered in natural language.

Notes