Source edition
Aristotle. Aristotelis Opera, Volume 1. Bekker, Immanuel, editor. Oxford: Oxford University Press, 1837.
Source data
A Digital Corpus for Graeco-Arabic Studies · CC BY-SA 4.0
Cloned and adapted by Humanitext, with ongoing edits.
Summary
This treatise presents a fundamental framework for classifying all entities and discourse in the world. Aristotle begins by organizing the relationship between language and reality, introducing the ten "categories" that classify everything that exists. In the first half, the work defines in detail the primary and secondary "substances" (ousia)—which serve as the foundation of all existence—alongside other major categories such as "quantity," "relation," and "quality," verifying their unique characteristics. In the second half, after briefly organizing the remaining categories like "action" and "affection," the discussion transitions from the categories themselves to the logical relations between terms. Here, the author analyzes the four types of opposition (correlation, contrariety, privation and possession, contradiction), the definitions of "prior" and "simultaneous," the classification of "motion," and the various meanings of "to have." Ultimately, the work establishes a systematic foundation of thought, moving from the analysis of individual entities to the clarification of logical relations.