Aristotle’s Organon

In modern circles, we speak casually of the “Scientific Method”, but this was not the original name of this method of investigation. In 1620, Francis Bacon called for the rejection of the “Scholastic Method” that was held by the Catholic Church, and urged modern society to embrace a method he titled the “Novum Organum“.  In Latin, this means “The New Method”. Assumed in this title is the existence of an old or existing method, which was the method of demonstrative investigation developed by Aristotle in the 4th century before Christ.  Aristotle’s “Organon” guided world philosophy and theology for 2,000 years before Bacon called for its rejection.

Aristotle is history's master of the art of Logic
Aristotle (384-322 BC) is history’s master of the art of Logic.

What is the “Organon”?

Aristotle’s “Organon” is the method or instrument to be used by men in the pursuit of philosophical knowledge.  Aristotle teaches this method through six books, which were called “the Organon“, as the 73 books of Sacred Scripture are called the “Bible”.  The books included in the Organon are accessible in our Academy Library:

Studying the Organon

In the Classical Liberal Arts Academy, we study classical Logic through a series of five “Classical Reasoning”  courses.  These courses treat of the six works of the Organon, plus an Introduction to the Categories by a 3rd century philosopher named Porphyry (234-305 AD).

For more information on classical Logic, please see the resources below.  If you have any questions about the study, please contact me.

Online Courses

All of the books of the Organon are studied in our Classical Reasoning Courses. You can study for free (without assessments), enroll in one of our courses (with assessments) or subscribe to our Student Plan (30 day free trial).

Articles on Aristotle’s Organon

  • Aristotle, On Interpretation. Chapter 3
    Prelection by Mr. William C. Michael In the first two lessons, we set out the goals for the study of Aristotle’s work “On Interpretation” and then learned about the Noun–the first of the two parts of enunciative speech. In this lesson, we study the second of the principal parts of speech: the Verb. Aristotle’s Text … Read more
  • Aristotle, On Interpretation. Chapter 2
    Prelection by Mr. William C. Michael In the previous lesson, we set out the goals for the study of Aristotle’s work “On Interpretation”. In this lesson, we zoom in and study the first of the principal parts of speech: the Noun. Aristotle’s Text Translated by Thomas Taylor Chapter 2. Of the Noun 1. A Noun … Read more
  • Aristotle, On Interpretation. Chapter 1
    Prelection by Mr. William C. Michael In this lesson, we begin our study of the second book of Aristotle’s Organon, “On Interpretation”. In this work we study “enunciative speech” and in this first chapter, Aristotle sets out the goals for this study. Aristotle’s Text Translated by Thomas Taylor 1. In the first place, it is necessary … Read more
  • St. Thomas Aquinas on Aristotle’s “On Interpretation”
    There is a twofold operation of the intellect. (1) One is the understanding of simple objects, that is, the operation by which the intellect apprehends just the essence of a thing alone; (2) the other is the operation of composing and dividing. There is also a (3) third operation, that of reasoning, by which reason … Read more
  • How the Socratic Method Directs the Scientific Method
    In this video, Mr. William C. Michael of the Classical Liberal Arts Academy puts ChatGPT to the test on the nature of light, which leads to a number of important conclusions. Mr. William C. MichaelClassical Liberal Arts Academy mail@classicalliberalarts.com For more resources from the Classical Liberal Arts Academy, visit: https://classicalliberalarts.com
  • Cicero on the Socratic Method
  • What is a Syllogism
  • Newman on Modern Students
    “The pleasurable excitement of reading what is new is their motive principle; and the imagination that they are doing something, and the boyish vanity which accompanies it, are their reward. They do not like Logic, they do not like Algebra, they have no taste for Mathematics; which only means that they do not like application, … Read more
  • Aristotle, On Interpretation. Chapter 09
    In this lesson, we will study chapter 09 of Aristotle’s work “On Interpretation”. translated by Thomas Taylor. To complete the objectives of this lesson, complete the following tasks: Study the Prelection. Read through the lesson once for familiarity. Study the lesson for mastery. Complete the lesson assessment. Prelection by William C. Michael Thus far, Aristotle … Read more
  • Aristotle, On Interpretation. Chapter 8
    To complete the objectives of this lesson, complete the following tasks: Read through the lesson below. Study the lesson for mastery. Complete the lesson assessment questions. Lesson Translation by Thomas Taylor. WHAT ARE SIMPLE ENUNCIATIONS? 1. The affirmation, however, and also the negation is one, which signifies one thing of one subject, either universal, if … Read more
  • Aristotle, On Interpretation. Chapter 7
    Of Universal, Particular, Indefinite and Singular Enunciations Chapter 7 of Aristotle’s work On Interpretation” is one of the most difficult chapters for students to understand. To complete the objectives of this lesson, complete the following tasks: Read through the lesson below. Study the lesson for mastery. Complete the lesson assessment questions. Lesson Translation by Thomas … Read more
  • Understanding Chapter 11 of Porphyry’s Introduction
    Students often have a difficult time understanding chapter 11 in Porphyry’s Introduction, but this is actually very simple. In the Introduction, Porphyry is explaining the five kinds of things that can be predicated of subjects, known as the five predicables: Genus, Difference, Species, Peculiarity and Accident. In chapter 11, Porphyry writes: “It would seem that … Read more
  • What is “Enunciation”?
    In the study of the art of Reasoning, we seek to understand the right ordering of the mind. We begin with Aristotle’s “Categories”, where we learn of the ten categories, which can be studied here. After learning of the categories, we take up the study of sentences in Aristotle’s “On Interpretation”, and we learn that … Read more
  • What are Aristotle’s “Ten Categories”?
    One of the most important achievements in the pursuit wisdom of by the ancients was Aristotle’s discovery of the “Ten Categories”. These are taught for the first time in human history in chapter 4 of Aristotle’s work titled “The Categories”. They are: Substance (or Essence) Quantity Quality Relation Location Time When Position Possession Action Passion … Read more
  • St. Thomas Aquinas on the Ends of Speaking and Writing
    “If man were by nature a solitary animal the passions of the soul by which he was conformed to things so as to have knowledge of them would be sufficient for him; but since he is by nature a political and social animal it was necessary that his conceptions be made known to others. This … Read more
  • What is Dialectic?
    As you learn about the seven classical liberal arts, you’ll notice a number of different names used to refer to the art of reasoning– “dialectic”, “logic”, “analytics”, or just “reasoning”. These names seem to be used with no distinction, yet they do not mean the same thing. In this video, I explain what “dialectic” is … Read more
  • Porphyry’s Introduction, Chapter 1 Prelection
    In the 5th century BC, ideas of democracy were growing in Greece and wise men saw a danger growing alongside them. As power moved into the hands of the people, opportunities opened for cunning men to deceive. These men, called “Sophists”, pretended to be wise in order to gain influence in society, and the common … Read more
  • The Principle of Non-Contradiction
  • Aristotle’s Prior Analytics PUBLISHED!
    I am happy to announce that I have re-published Taylor’s translation of Aristotle’s Prior Analytics in a number of useful formats for students in the Classical Liberal Arts Academy. This is the most important of all studies in the classical liberal arts, and we now have a searchable, working text on the Academy website–and a … Read more
  • Classical Disputations: How to Make Conversation Productive
    This is William Michael of the Classical Liberal Arts Academy. Tonight I’d like to talk about a topic that I believe can radically improve conversation among Christians and non-Christians. It’s a topic that I taught, it was in my last private school teaching job, and it was the result of my teaching on this topic … Read more
  • Aristotle, Prior Analytics. Book I, Chapter 1 Tutorial
  • What is Logic?
    One can find many articles and videos in which men who identify themselves as “classical educators” or even “philosophers” provide very bad answers. If, however, they actually studied the writings of history’s masters, they would know that St. Thomas Aquinas already answered this question far more eloquently than any of them can, and if they … Read more
  • Porphyry, Introduction, Chapter 17. Comparison of Peculiarities and Accidents
    In this lesson, we complete the reading of Porphyry’s Introduction. We study the similarities and differences of peculiarities and accidents. To complete the objectives of this lesson, complete the following tasks: Study the lesson for mastery. Complete the lesson assessment. Lesson 1. It now remains to speak concerning peculiarity and accident; for we have already … Read more
  • Aristotle, Categories (Full Text)
    Contents Chapter 1. Definitions Chapter 2. Divisions Chapter 3. Rules Chapter 4. Of the Ten Categories Chapter 5. Of Substance Chapter 6. Of Quantity Chapter 7. Of Relatives Chapter 8. Of Quality Chapter 9. Of Action, Passion & Remaining Categories Chapter 10. Of Opposites Chapter 11. Of Contraries Chapter 12. Of Priority Chapter 13. On … Read more
  • Modern Science and Classical Catholic Education
  • Aristotle, Categories. Chapter 8, Of Quality
    In this lesson, we continue our study of Aristotle’s ten Categories. Having studied Substance, Quantity and Relatives, we move on to Quality in chapter 8. Translation by Thomas Taylor 1. I denominate Quality that according to which certain things are said to be of such kinds. 4. But habit differs from disposition in this, that … Read more
  • Porphyry, Introduction. Chapter 2
    1. It seems that neither Genus nor Species is simply denominated. Of Genus 2. For a collection of certain things, subsisting in a certain respect with reference to one thing, and to each other, is called Genus; according to which signification the Genus of the Heraclidae is denominated from the habitude from one thing, I … Read more
  • Free Book! Porphyry’s Introduction
    We’re happy to provide Academy students with another newly published book: Porphyry’s Introduction to the Categories of Aristotle. This 3rd century classic is the first book studied in the Classical Liberal Arts Academy’s Classical Reasoning I course. You can download a free copy below, or purchase a printed copy from the Academy bookstore. God bless … Read more
  • What the Summa Theologica Teaches Us about Writing
  • Aristotle, Categories. Chapter 3
    In this lesson, we study the third chapter of Aristotle’s Categories. Study the lesson for mastery, using the notes and comprehension questions as a guide. Translation by Thomas Taylor When one thing is predicated of another as of a subject, as many things as are spoken about that which is being predicated, can also be … Read more
  • The Porphyrian Tree or Tree of Porphyry
    One of the most important (and difficult!) obstacles for students in classical Logic is understanding an illustration known as the “Porphyrian Tree” or the “Tree of Porphyry“. This illustration explains how Aristotle’s “Categories” are divided from the “genus most general” down through all subalternate genera and species, down to the “species most special” and individuals. … Read more
  • Poprhyry, Introduction. Chapter 3, Of Difference
    Having studied Genus and Species, we move on to the study of Difference in chapter 3. Translation by Thomas Taylor Difference, however, is predicated (a) in common, (b) peculiarly, and (c) most peculiarly. 1. Simple Differences A. Common Difference (a) For one thing is said to differ from another in common, in consequence of differing … Read more
  • Aristotle, Topics. Book I, Chapter 2
    Translation Translation by Thomas Taylor To what has been said in chapter 1, it will be consequent to show in what the ability of this treatise consists, and how far its utility is extended. It is useful, therefore, to three things: to exercise, to common conversation, and to philosophic sciences. That it is useful indeed … Read more
  • Aristotle, Topics. Book I, Chapter 1
    Translation Translation by Thomas Taylor The design of this treatise is to discover a method by which we may be able to syllogize about every proposed problem from probable arguments; and so that we ourselves sustaining the controversy, may assert nothing repugnant. In the first place, therefore, let us show what a syllogism is, and … Read more
  • Aristotle, On Interpretation, Chapter 3
    In this lesson, we study the third chapter of Aristotle’s treatise On Interpretation, the second book of the Organon. For tutorial resources on this lesson, please see the Academy YouTube channel. This lesson is studied in the Academy’s Classical Reasoning I course. The text below is adapted from Thomas Taylor’s translation of Aristotle’s Prior Analytics … Read more
  • Aristotle, On Interpretation, Chapter 2
    A Noun, therefore, is a sound significant from compact, without time, of which no part taken separately is significant.[ref]”Aristotle posits five parts in the definition of the name. “Vocal sound” is given first, as the genus. This distinguishes the Noun from all sounds that are not vocal. The second part is the first difference, i.e., … Read more
  • Aristotle, On Interpretation
    Before getting started in the study of Aristotle’s “On Interpretation”, students should read the introduction by St. Thomas Aquinas. Chapter 1. Introduction 1. In the first place, it is necessary to determine what Noun and Verb are; and in the next place, what Negation, Affirmation, Enunciation, and a Sentence are. 2. Those things which are … Read more
  • Aristotle, Prior Analytics, Book I, Chapter 3
    In this lesson, we study the third chapter of Book I of Aristotle’s Prior Analytics, the third book of the Organon. For tutorial resources on this lesson, please see the Academy YouTube channel. This lesson is studied in the Academy’s Classical Reasoning II course. The text below is adapted from Thomas Taylor’s translation of Aristotle’s … Read more
  • Aristotle, Prior Analytics, Book I, Chapter 2
    In this lesson, we study the second chapter of Aristotle’s Prior Analytics, the third book of the Organon. For tutorial resources on this lesson, please see the Academy YouTube channel. This lesson is studied in the Academy’s Classical Reasoning II course. The text below is adapted from Thomas Taylor’s translation of Aristotle’s Prior Analytics Since, … Read more
  • Aristotle, Prior Analytics, Book I, Chapter 1
    In this lesson, we study the first chapter of Aristotle’s Prior Analytics, the third book of the Organon. For tutorial resources on this lesson, please see the Academy YouTube channel. This lesson is studied in the Academy’s Classical Reasoning II course. The text below is adapted from Thomas Taylor’s translation of Aristotle’s Prior Analytics In … Read more
  • Porphyry, Introduction. Chapter 1
    Since it is necessary, to the doctrine of the Categories of Aristotle, and to the formation of definitions, and in short, to those things which pertain to division and demonstration, to know what Genus and Difference, Species, Peculiarity, and Accident are; and since also the theory of these is useful, in a summary way, I … Read more
  • What is the Socratic Method?
    The Socratic Method is spoken of today in a thousands different contexts.  Some speak about the “Socratic Method” as a way of teaching classes in schools.  Others speak of the “Socratic Method” as a way of solving problems.  What should concern us is that most of the people who are talking about the Socratic Method … Read more
  • Getting Started with the Study of Logic
    The most important study in the classical Catholic curriculum is, without question, the art of Reasoning.  In the Classical Liberal Arts Academy, we study all of Aristotle’s works on the subject, contained in his famous “Organon”.  I believe this first video, introducing Aristotle’s Categories, give a good introduction to the challenges of the study, and … Read more