CARS Lesson 10  —  The main idea
What is the main idea?

The proposition that there will always be a main idea depends on two premises: that every piece of writing is an argument and every argument has a central thesis. You may run into a passage occasionally where it doesn't seem that way. The author may be exploring a set of ideas. Some essays are historical or biographical narratives where there is a theme instead of a main idea. If it's difficult to determine the main idea, ask yourself why the author sat down to write the essay. This is a good place to start.

For most passages, it's fairly straightforward. Many essays ARE working to establish or justify a central claim. They have a thesis. There may even be a thesis statement. The purpose of the writer in sitting down to write the essay was to present rational grounds for justified belief in their thesis. They are trying to convince you. That's the main idea!

For any CARS passage, the working assumption should be that there definitely is a main idea and you need to figure out what it is. For every passage, consciously determine the main idea before moving on to the questions. If you make a discipline of this, you will find many of the questions much easier. This applies not only to the 'main idea' and 'thematic extension' types of questions but the other types as well.

How to determine the main idea of a passage
  • Look at the whole passage

    In earlier lessons, we described the crucial step after reading the passage but before moving on to the questions. We can finally see the passage as a whole. We move through the passage quickly from top to bottom to answer the question, "What are the parts of this thing?" This step refreshes your memory of many details, and it gives you a firmer sense of the structure of the argument. The structure of the argument was created by the author as a vehicle to support the main idea. Seeing the structure of the argument at this stage often gives you a clear understanding of the main idea.

  • What kind of argument is it?

    In seeking to determine the main idea, as a starting point, it can be very clarifying to recognize the kind of argument the passage represents. Is it an argument of fact, an argument of definition, an argument of evaluation, or a proposal? For example, when you see that you are dealing with an argument of fact, you can ask yourself, "What is the issue at stake? Where does the author stand? What is their hypothesis?" It can likewise be very clarifying to recognize a passage as an argument of definition, where the main purpose is to assign attributes or class membership to an idea or thing. If it's an argument of evaluation, the main idea is often the verdict of the author's rational or aesthetic judgment. If it's a proposal, the main idea may simply be advocacy for a change in policy or practice.

  • How is the argument structured?

    After seeing the passage as a whole and recognizing its overall structure, you will often gain reinforcement of your sense of the main idea. If the argument was persuasive, you will see how the different parts of the passage made it successful. If the argument was not successful, you see what the author tried to do. Rhetorical analysis is a mode of critical reading in which you "see how the sausage is made". The main idea is the central claim of the argument. In a classical argument, the central claim is called the thesis. You see the portions of the argument providing warranted evidence for the thesis and the portions providing support in the form of logical reasoning. You see the portions where the author conditions their claim or provides exceptions and where they deal with counter-arguments. You see how it all serves the main idea. You've done your job. You're going to move through the questions for this passage quickly.

  • Be careful to distinguish counter-arguments

    In our experience, one of the most significant pitfalls on the way to the main idea of a passage is to mistake the author's presentation of a counter-argument for the author's own point-of-view. For example, in Rogerian argument, there is a norm in seeking common ground to state the views of opposing positions in a way that demonstrates true consideration of their merits. The counter-arguments in Rogerian argument often appear towards the beginning of the passage, after the general introduction of the problem. It's very important to pay careful attention to the tone of the writer. Oftentimes, the writer will signal critical distance from a position with phrasing such as 'Historians have long believed that . . .' or 'There are good arguments for . . .' It can be subtle. Cultivate an openness to the author transitioning out of this mode. When they take a stronger, more declarative mode in a later paragraph, they are revealing their own point-of-view in the argument.

    It can be even more subtle in arguments that have a dialectical structure. Instead of following the classical pathway starting with thesis then evidence then counter-argument then conclusion, the dialectical rhetorical figure starts with thesis then antithesis then synthesis. Dialectic is a favorite approach for writers in the world of continental philosophy (modern philosophy from the French and German speaking worlds) and critical theory. In this type of essay, it can seem like the author went out on a limb with the thesis only to saw it off. The thesis turns out not to be the main idea after all. It's in the synthesis. Where you wind up at the end is not where you expected you'd be. This is known as deconstruction or post-structuralism. It helps with this kind of essay to imagine an internal debate that is always striving to transcend itself. Go with the flow and don't be over-awed by the writer's dance and you'll be okay. At their most difficult, these can be very difficult. The ones that occasionally make it to the MCAT aren't so bad.

    The point with both Rogerian and post-structuralist styles is to bring an openness to recognize the passage as an exploration through a kind of dialogue on the way to the main idea. As different points of view are explored, pay careful attention to the author's tone, the strength of evidence, and the questioning of the warrants of evidence. Look for where the author 'inhabits' the argument instead of 'positing' the argument to later pivot from. Often it's in the tone where you find confirmation of the author's point of view and the main idea.

Let's practice

Begin working through Step 2 and Step 3 of the CARS Diagnostic Tool. Pace yourself to complete the curriculum provided by this resource within the next four modules.

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