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PHIL 109


  • Course ID:PHIL 109
  • Semesters:1
  • Department:Philosophy
  • Course Rank:Required
  • Teachers:Mark Grannis

Description and Objectives

This course is an introduction to Logic, which we can define provisionally as both the science and the art of sound reasoning. We will cover both Formal Logic, which deals with the form or structure of our reasoning, and with Material Logic, which deals with the content of our reasoning. Together, these branches of Logic teach us how we can (or sometimes why we cannot) reason from one piece of knowledge to a new truth not previously understood. Logic is a traditional cornerstone of a liberal arts education, and it is the crucial first step in the philosophy sequence in the Upper School at The Heights.

By the end of this course, you will:

  • learn how to identify, analyze, and construct sound arguments, as well as how to detect and refute unsound arguments;
  • cultivate a habit of logical thought;
  • strengthen your ability to read and listen closely, think lucidly, and write and speak clearly; and
  • build a solid foundation for more advanced philosophy courses—and in fact, for all future learning in any field for the rest of your life.


Our primary text will be subject Martin Cothran, Traditional Logic I (3rd 2017, ISBN 978-1-61538-876-9), supplemented with short treatments authored by Mr. Grannis. We may also look from time to time at popular essays from the public domain or current periodicals.

Outline of Topics Covered

  • Unit 1: Knowing What We’re Talking About
  • Unit 2: The Furniture of the Universe
  • Unit 3: Definition and Division
  • Unit 4: Simple Categorical Propositions
  • Unit 5: Categorical Syllogisms
  • Unit 6: Compound Syllogisms
  • Unit 7: Advanced Deductive Reasoning
  • Unit 8: Inductive Reasoning
  • Unit 9:  Informal Fallacies
  • Unit 10: Irrationality

Course Requirements

Our course will meet every other school day, alternating with your religion course. This means that in the course of the year we will cover about a semester’s worth of material. You should expect to have a reading assignment almost every class, together with frequent low-stakes quizzes and two to three unit tests per quarter. Your quarterly grades will be based on your performance on quizzes and tests, the quality of your class participation, and any extra-credit projects you complete. Quizzes will test your retrieval based on the readings, but all unit tests will be open-note, so take good notes. There will be a cumulative midterm before Christmas and a comprehensive final examination at the end of the school year.

Some teenagers at other schools might be tempted to become more argumentative at home after studying Logic at school.  Those who study Logic at The Heights will of course keep in mind that the tools learned in this class are for declarative propositions only—not for imperatives (“Turn out your light now”) or interrogatives (“Did you take out the trash?”). If you misapply your learning at home in any way your parents find distressing enough to report to your instructor, your grade may be affected, in rough proportion to the heat of the conversation.

Successful Students

Logic is highly cumulative, so your long-term success depends critically upon your diligence in (1) reading and comprehending the daily lessons as they are assigned; (2) following the examples worked out in class; (3) asking questions in class to clarify any areas of confusion; and (4) integrating each new element into the body of material already learned. If you focus on those four things, you will succeed brilliantly.

If the readings leave you confused, that is all the more reason to read them in advance, so you can bring your questions to class. If you need any help understanding the material after we have gone over it in class, please contact me right away so that we can get to the root of the misunderstanding and provide additional practice or instruction where appropriate. I am generally available in my office at The Heights during first and second periods, but if that doesn’t work for you I promise we will find time to meet if you contact me by e-mail or phone.

This is a great course. You will use it every day for the rest of your lives.