A Short Course in Logic - Introduction

 

Why bother with Logic?

 

Chances are pretty good that you’ve already had some philosophical conversations, either with yourself or with other people. Think back to some of those long talks about the existence of God, the nature of reality, the meaning of life, the possibility of love, the essence of morality, or anything like that. Hopefully, you enjoyed those conversations. But no matter how enjoyable they were, I bet they were confusing on some level.

 

Philosophical questions are a lot like beautiful, green forests. They’re so attractive that it’s hard to resist walking into them. And the further you walk, the darker things get and before very long you’re lost or walking in circles.

 

Learning a little logic is a lot like learning how to use a compass and a map. Learning how to use a compass and a map might not be quite as exciting as exploring the woods, but it makes exploring the woods a lot easier and more enjoyable. Similarly, learning a little logic might not be quite as exciting as the philosophical questions we’ll be studying, but it gives us a framework we can use as we tackle those interesting philosophical questions. And without some kind of framework like this, it’s very easy to get lost or to find ourselves going in circles.

 

Studying logic is also important in its own right. For one thing, I find it enjoyable and hopefully you will too. For another thing, learning even just a little logic can help you to think a lot more clearly in every area of your life. So it’s definitely worth our while to take some time to learn logic before we jump right in to deep philosophical questions.

 

A Quick Overview

 

The general idea behind the logic we’ll be studying is that we can represent a piece of philosophical reasoning with a diagram that exposes its components and the relationships between these components. This, in turn, will help us to better understand and evaluate the piece of reasoning.

 

For the purposes of the philosophical readings we’ll be seeing, you’ll want to be able to

1) recognize the parts of a piece of philosophical reasoning when it’s written as a normal passage,

2) understand the diagram of a piece of reasoning, and

3) evaluate a piece of reasoning when presented with its diagram.

 

This “mini” course in logic is designed to give you these skills.

 

And here’s an important study tip: As you progress through this lesson, please do not worry about taking notes. If you know that you happen to learn better that way, of course, then by all means take notes as you go along. But you don’t have to take notes because

·         there will be a summary of what we’ve learned at the end of each example, and

·         there will be a cumulative summary at the end of the lesson.

Plan to print out these summaries in lieu of writing things down. Your only job as you work through this lesson is to focus on understanding what we do.

 

Let’s take a look at Example 1.