LA 1200 · Trivium: The School of Logic — Module 5: The Categorical Syllogism

Led by Boethius Simulacrum

Two statements joined by a shared term yield a third that neither contains — necessarily, if the shape is right. The centre of the art, and the discovery that validity never consults subject matter.

1. Module 5

   The Categorical Syllogism

   Led by Boethius Simulacrum

   The question

   Eight sittings. You begin by putting a sound argument beside an

   Outcome

   The student can identify the figure and mood of any categorical

   Sub-units

   1. ○ 5.1 Validity Is a Matter of Form Open this unit → ✓ ↻
   2. ○ 5.2 Terms, Figures, Moods Open this unit → ✓ ↻
   3. ○ 5.3 Distribution Open this unit → ✓ ↻
   4. ○ 5.4 The Rules Open this unit → ✓ ↻
   5. ○ 5.5 The Valid Moods and the Verses Open this unit → ✓ ↻
   6. ○ 5.6 Reduction to the First Figure Open this unit → ✓ ↻
   7. ○ 5.7 Enthymemes: Arguments as They Actually Occur Open this unit → ✓ ↻
   8. ○ 5.8 Testing Live Arguments Open this unit → ✓ ↻
   Begin the course → Print certificate of completion

   Practice scenarios

   The Hiring Committee

   A committee is defending a decision. Their reasoning: *We want candidates who will stay. People who have stayed in previous roles will stay. This candidate stayed in her previous role. So she will stay.* One member objects that this is circular. Another objects that it is invalid. A third says it is fine and the dissenters are being difficult. They have asked you to say who is right, and the meeting is running late.

   Your goals

   • Reduce the argument to standard form and identify what is actually claimed
   • Determine whether the circularity objection is correct, and if not, name what
   • that objector has actually noticed
   • Determine whether the argument is valid, and if not, name the rule violated
   • Identify any suppressed premise and state it in its weakest adequate form
   • Say precisely what the committee is entitled to conclude, and what it is not

   Practise this scenario →