Categorical Propositions
Learn about the categorical propositions worked out by Aristotle.
Aristotle’s contribution to logic
Aristotle was a citizen of the ancient Athenian world but is still a household name around 2,400 years later. That’s an astonishing feat in itself. His name lives on because of his work. Besides other contributions, one of his biggest is in the formal study of logic. He belonged to one of the most famous chains of teacher-student philosophers, all of whom are household names, including Socrates, Plato, Aristotle, and Alexander the Great. This was a dialogical world, which assumed that the nature of truth is such that it can be established through the process of dialogue and the rules of deductive logic. While Socrates and Plato engaged and documented dialogues in various public settings, Aristotle studied dialogues and human language formally. His efforts resulted in the first mechanization of the process of logic, which we use to arrive at valid and invalid arguments (or correct and incorrect forms of reasoning, respectively). He began the mechanization or automation of logic by scoping (or limiting) his study to only categorical propositions.
Propositions to categorical propositions
All of these Greco-Roman philosophers were interested in the definitions and etymological roots of words. They believed that a relation exists between reality, language, and logic and that language allows us to speak of different subjects or beings. In other words, we can speak of categories and, through our sentences, bring two different categories into a relationship; for example, humans and mammals are two categories. This was an important realization of their dialogue-based deductive theory of knowledge.
In time, Aristotle studied dialogues and the way people used sentences in their everyday arguments, and eventually extracted a bare minimum relational template for a sentence, which is as follows:
Firstly, this contains two familiar terms: