Tutorial One, Chapter One

The Goals
of Symbolic Logic

There is much we can learn from symbolic logic. It will help make us more proficient thinkers and help us better understand symbolisms and the role formal thinking can play. Mostly, though, we shall have to wait and see what we can learn from logic. (Just as one cannot well understand the role of mathematics in science without the examples, we need to develop the logic first to see how it can be useful.)

However, we can get some understanding of symbolic logic's value
by introducing one main goal of this course: *to develop clarity and precision
of thought.* At the same time, we will see how tutorials and exercises
work in the Logic Café.

Begin with a *very* easy example:

Suppose we know: Chris will get an 'A' *or* a 'B' in logic.

Later we discover: Chris will *not* get an 'A'.

We conclude: ???

The answer is obvious: **Chris will get a 'B'**.

The idea is that Chris gets one of these two grades, so if it's not an 'A', then it must be a 'B'.

(This is a "* sidebar*" for extra hints,
warnings, or asides. You'll see it from time to time.)

Click to close this box.

But what's the principle involved behind this thinking? Click on the idea which best fits the thinking about Chris:

- If two claims are both true, then they are true.
- If one of two possibilities is true and it's not the first, then the second possibility is true.
- If one tries hard, one gets what one deserves.

(This is multiple choice: click on the correct answer of 1. through 3. Notice that directions appear in this different type face.)