What purpose does a thesis serve in an essay? What function does it perform? A thesis is the core of an essay. It serves as a backbone, supporting an essay's argument or purpose. Following are two examples which illustrate what this means.
The minimum wage in a town or county should be set according to the cost of living, rather than being decided by the federal or state governments.
With your thesis in mind, you look for research to support your argument. However, most of what you find is arguments against a minimum wage, including articles that promote a free market approach to wages and others that assert that laws compelling employers to pay minimum wages violate their civil rights.
If you don't maintain your focus on your thesis, you might be distracted by these arguments and turn your essay into a discussion of civil liberties. If you remain focused on your thesis, however, you will continue your research until you locate sources related to your argument.
Here's another example. Suppose you are writing an informative essay about the difference between foods labeled "organic" and those that are labeled "natural." Your thesis — the core of your essay — is the following:
Foods labeled "organic" must be certified, and while this certification can be falsified, "organic" is a more meaningful label than "natural," which, from a legal perspective, doesn't mean anything.
As you write that Twinkies can be considered natural since theyre made from corn, you get sidetracked. You begin to lecture your readers that the companies that produce food like Twinkies don't care about their customers; they only care about their "bottom line."
Your Twinkie tirade is well-written, but when you check your thesis, you remember that you're supposed to be writing about organic and natural labeling. You've gone off track, but revisiting your thesis, brought you back on track. Perhaps there will be a place for those passionate lines about evil companies in another essay.
In addition to serving as the backbone of an essay, the thesis must also be the answer to an important question: a question that is worth asking. Whenever you write an academic essay, your goal is to participate in a broader academic conversation. No one wants to join a conversation by stating something that is obvious, or by arguing for a foregone conclusion. What would be the point of doing so? "So what?", readers might ask.
Thesis statements like the one in the previous example are why experienced writers and teachers advocate the use of "so what." Writers should ask themselves this question whenever they're developing a thesis. "So what?" is one of several questions that you should ask yourself during the writing process:
If your friend in the example above had asked herself "so what?", she might have developed a more specific thesis about racism. For example, if she'd gone beyond the basic assumption that "racism is bad" and asked herself how to solve the problem, or what causes racism — both questions worth asking — she might have formulated a worthwhile thesis.
The occasion for writing is the set of circumstances that lead a writer to undertake a writing task, including the rhetorical situation, assignment requirements, and other elements. Thinking about the occasion for writing is another way to consider the rhetorical situation of a written work, except that the occasion for writing also focuses on the prompt, assignment, or task.
To understand the occasion for writing in a composition class, you must consider the writer's purpose within and beyond the assignment. The presumed audience (including the instructor/evaluator and, possibly, others), the cultural and historical context (and how it influences topic choice), and the writer's background, must all be taken into account.
The assignment topic is broad, but since this is an area in which you have interest, you propose the thesis stated above, even though there are easier (and more effective) theses you could have chosen.
This example demonstrates the breadth and depth of information and observation required to understand the occasion for writing of any project.
Source: Adapted from Sophia Instructor Gavin McCall