Scott Postma

A blog about the Great Books, the Craft of Writing, and Human Flourishing.

Saturday School: Lesson #5 – Supporting Your Thesis, Part 1 (Definition)


Lesson #5 – Supporting Your Thesis Statement I (Definition)

  1. Complete the reading assignment
  2. Complete the writing exercise
  3. Post your assignment in the comments
  4. Share the lesson with a friend


One last reminder, in case you’re just joining us: we are focusing on the persuasive essay because good writing must have a compelling message. Later, we will discuss other genres, like fiction and poetry. But right now we are going to focus on the fundamental elements of our craft.


Last week I introduced you to the thesis statement. A thesis is a proposition that argues something about your topic. It is more than your opinion or impression about your topic. It is a statement your reader can refute or affirm.

Typically, your thesis will be a single declarative sentence you provide in the Exordium (your introduction). Your thesis will set the trajectory for your paper. It is the single statement in your paper that all other arguments will support.

Like a map, a good thesis will be “determinate enough to ensure unity and coherence.”1

Today’s Lesson

In this lesson, I’ll begin discussing the ways you must support your thesis.

First, since the thesis is the declarative assertion you are making about your topic, you will have to support your proposition with proofs.

When we were young, our parents sometimes used the “because I’m the parent and I said so,” argument. That’s good enough for small children who want to argue the benefits of not making their beds and such, but it will never do for writers who are trying to persuade their readers to believe their assertion.

You must have real and reasoned arguments to support your thesis.

Second, never assume your proposition is self-evident. Just because a proposition is obvious to you doesn’t mean it is obvious to your reader. Without being condescending, explain what is obvious to you.

Your well-written will essay will define the terms and develop the ideas that support your thesis.

Third, your defined and developed arguments will have to make sense of the topic or object you are analyzing. That could be a political or religious position, for instance, or a text or film you are analyzing.

The point is your defined and developed arguments must relate to your object in a distinct way. We’ll discuss this point in a later lesson; today I want to touch on definition, and the following weeks on the proper methods of developing an idea.

Definition simply means clarifying terms, ideas, and positions for your reader.

For example, if you were analyzing the presidency of Abraham Lincoln, let’s say, and intended to argue that our sixteenth president was a politician rather than a statesman, it would be incumbent upon you to explain to the reader what you are asserting exactly by making clear the distinction between the terms politician and statesman.

As you can see, terms that have similar meanings, and that are sometimes used interchangeably, actually have important nuances that sometimes need to be clarified. In this case, it’s actually at the root of the thesis. Hopefully, this helps demonstrate why one of the most important aspects of supporting your thesis is to clarify terms.

Writing Exercise

Using the thesis statement you wrote last week, write a supporting paragraph that explains the key terms and positions you are using in your thesis. These may or may not be dictionary definitions. In some cases, these may even be your own nuanced usage of the terms. Don’t worry about transitions, for now. Just write some clarifying sentences. You can revise them at a later time.

Example: Students who hope to succeed in life and work must master the craft of writing before graduating high school. By succeed, the reader should not assume it is meant something like a six-figure income, per se; although, that could be part of the reward. Rather, success here refers to quality of life, or one’s feeling of meaningfulness, or satisfaction of being. To succeed in life and work means having rightly realized and embraced one’s universal and particular humanness–and knowing the difference between them. (There’s much more that can be said here, but you get the idea.)

Now it’s your turn. Post your paragraph in the comments.

Do you want to touch readers with your words, learn the craft of writing, or simply improve your writing skills from a classical perspective? Join me each week for Saturday (Writing) School. Every Saturday I’ll send a lesson to your inbox you can complete in an hour, or you can work on it at your leisure. It’s free!


1Crider, Scott F. The Office of Assertion: An Art of Rhetoric for the Academic Essay. Wilmington, DE: ISI Books, 2005.

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About Scott Postma

Scott is a writer and teacher living in North Idaho. He loves teaching the Great Books, writing and blogging, and collecting more books than he’ll ever read in a lifetime. You can subscribe to the tribe and follow him on Twitter, Facebook, and Google Plus.

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