The Organon: Aristotle's Logic
The Method of Philosophy
- Texts of the Organon:
Note: 'Organon' is Latin for "instrument"
- Categories - Aristotle on Substance
- On Interpretation - The parts of, and types of, propositions
- Prior Analytics - The general theory of deductive inference
- Posterior Analytics - The nature of demonstrative reasoning and definition
- Topics - The problems inherent in dialectical reasoning
- On Sophistical Refutations - The nature of fallacious reasoning
- The Purpose of the Organon:
- To discover and explicate the forms of reason common to all sciences
- Popular -
- To give instruction in the efficient forms of argument and reason
- The Categories: "What is it that is?"
Note: 'kategoria' means "statement of charge," or "assertion," or "predication"
- The Use of Names -
- Homonyms - same name, different definition
- Synonyms - same name, same definition
- Paronyms - names derived from a predicate
- Three kinds of "things" ('onta') -
- That which is said "of" something - "Socrates is a man."
- That which is said to "be in" something - "Socrates is white."
Note: There is a special category of things which can be both said "of" and "in" a subject - "Socrates is knowledgeable of grammar."
- That which is neither said "of" nor "in" something - "Socrates"
- Two Kinds of Substance -
- Primary Substance - That which is neither said "of" nor "in"
- The cause of all secondary substance (contra Plato)
- All primary substances are equal
- Only primary substance signifies a real thing (a "this")
- Primary substances are neither more nor less
- Primary substances allow contrary properties (because of change)
- Secondary Substance - The species of a primary substance
- On Interpretation: The Square of Opposition
- The Components of language -
- Words - symbols of ideas in the mind (spoken or written)
- Nouns ("names") - conventional symbols for things
- Verbs - temporal symbols of predicates (that which is said "of")
- Sentences - a meaningful compound of symbols (some of the symbols [i.
- , nouns] being independently meaningful)
- Proposition - a sentence which has a truth-value
- The Four kinds of Propositions -
- Universal Affirmative (A)
- Universal Negative (E)
- Particular Affirmative (I)
- Particular Negative (O)
- The Logical Relationships between the four propositions -
- Contrary opposites
- Contradictory opposites
Note: The four categorical propositions along with their four relations creates the "Square of Opposition."
- Other Derivative Logical Relations -
- The Law of non-contradiction (18a35)
- The necessity/contingency distinction (19a20ff)
- The Posterior Analytics: Deductive and Inductive Reasoning
- Scientific Knowledge ('episteme') - understanding the necessary cause of an event (a "thing")
- Two Forms of Dialectical Reasoning - The Method of Scientific Knowledge
- Syllogism - From Universal to Particular propositions
- Induction - From Particular to Universal propositions
- Universal Categorical propositions are derived from sensory experience
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