Teaching Logic

The study of logic which usually begins in the 6th or 7th grade can be divided into formal and informal (sometimes called “material”) logic. Informal logic is simply about practical, solid reasoning and argument. It includes Informal fallacies such as Ad Hominem, Chronological Snobbery, and Equivocation that have more to do with the actual meaning of the words.The study of formal logic starts with deductive logic and discussed whether or not an argument is valid (whether the logic works, not so much whether it is true). Classical courses nearly always cover Aristotelian (syllogistic) logic. This form of logic involves putting things in categories. For example: 1) All students are human 2) Some children are students 3) Therefore, some humans are students.

Most also cover a more difficult and widely-known form of deductive logic called propositional Logic. It takes statements that are either true or false and uses symbols meaning things like “if…then, either…or, not, if and only if.” It includes formal fallacies such as Modus Ponens. This type involves logical proofs. In addition, some courses cover truth tables and truth trees. Most courses cover inductive logic as well. They do not usually cover modal logic or predicate logic.

In formal logic, math meets language in syllogisms and proofs. Some logic is highly mathematical, leading into computer languages, operands, or calculus. Although there is plenty room for this in a classical program, many of the specifically classical texts focus on the lingual, rhetorical side of formal logic.

Logic Curricula 

• Introductory and Intermediate logic – These books published by Logos Press teach both formal and informal Logic. They are ideal for teachers who are unfamiliar with the subject matter and want a simple and complete text that includes both lessons and worksheets.

• The Amazing Dr. Ransom’s Bestiary of Adorable Fallacies – This is a fun book of informal fallacies for any age.

• Art of Argument – This is Classical Academic Press’ informal logic book which can be followed by either of their other texts.
• Discovery of Deduction – This is CAP’s formal logic text.
• Argument Builder – Also by CAP, this is a mix of logic and rhetoric, not really a logic course. 

• Material Logic – This is Memoria Press’ curriculum that covers informal logic only.
• Traditional Logic 1 and 2 – This is Memoria Press’ formal logic curriculum which focuses on aristotelian logic. 

• The Fallacy Detective and The Thinking Toolbox – These are simpler texts that cover informal logic in its most practical manifestations.