Aristotle's Logic - Introductory article by Garth Kemerling.
Meta Description: [ A survey of the history of Western philosophy. ]

Aristotle's Reform of Paideia - Article by Evelyn Barker, arguing that the principal aim of Aristotle's Organon was to reform the contemporary paedagogical role of dialectic.

Earliest Uses of Symbols of Set Theory and Logic - Explains the early introduction of notations used in logic and set theory as we know it today. Includes reference links to key people in this area.

Logic - Entry in the Catholic Encyclopaedia (1917), dominated by a historical survey from Indian and Pre-Aristotelian philosophy to the Logic of John Stuart Mill.
Meta Description: [ A historical survey from Indian and Pre-Aristotelian philosophy to the Logic of John Stuart Mill ]

Mediaeval Logic and Philosophy - Resource maintained by Paul Vincent Spade at Indiana University.
Meta Description: [ For scholars and students of mediaeval logic and philosophy. E-mail addresses, links, bulletin board, things to download. ]

Medieval Theories of Analogy - Entry in the Stanford Encyclopaedia of Philosophy, by E. Jennifer Ashworth.

Medieval Theories of Modality - Article at the Stanford Encyclopaedia of Philosophy.

On Dialectic - By St. Augustine. Latin original together with translation by J. Marchand.

Peter of Spain (Petrus Hispanus) - Life and work of 13th century logician and author of the Tractatus; from the Stanford Encyclopedia by Joke Spruyt.

Scholastic Logic - Chapter Two of Joseph Perrier's The Revival of Scholastic Philosophy in the Nineteenth Century (1909).

Scholasticism - Online text by Joseph Rickaby (1908).

Square of Opposition - Article in the Stanford Encyclopaedia of Philosophy, by Terence Parsons.

Syllogistic logic online - This site contains an online program for studying Aristotle's syllogistic logic. The theory of Aristotle's ancient logic is also presented.
Meta Description: [ SYLLOGISM: This site allows online experimentation with Aristotelian term logic, especially syllogistic reasoning. All the rules of Aristotelian logic have been implemented.Thus automatic proofs are possible. There is also a constru... ]

The Summulae of John Buridan - A critical introduction by Gyula Klima.