A thesis is the main claim you are making in an argument, similar to the hypothesis in a scientific experiment. It is what you are trying to prove or persuade your audience to believe or do. It’s helpful to develop a working thesis to guide your composition process. “Working” is the operative word here; your ideas are likely to change during research and the composing process, but beginning with a plan will help you stay focused.
In an informative essay or speech, you may not need a thesis statement, per se, because you’re not trying to prove anything. You will, however, still need to have a clearly articulated main, or controlling, idea. That idea is the primary message you’re trying to convey to your audience.

Formulating a Working Thesis

You will be refining your working thesis as you think about or research your topic. Most likely, you will be adding detail and making it more specific. It should mention two things: the topic and your comment about the topic. You can make the statement more specific later, but at the beginning just get the basics down.
Ex. Working Thesis Public school vouchers should not only be allowed but encouraged by the federal government.
Ex. Working Main Idea Public school vouchers are growing in popularity among parents but are still opposed by teacher unions.
 
In these examples, the topic is at the beginning of the sentence (public school vouchers) and the writer’s statement or opinion about the topic is at the end.
Below are some questions that can help you move from topic to working thesis. If your topic is organic farming, for example, think about whether you can define, classify, or compare it to something:

• Define: Explain a complex term’s meaning. Select words with disputed definitions or words that lend themselves to extended, thoughtful definition, such as “life” or “intelligence.”
• Classify: Explain a topic by categorizing it with like items. Athletes can be placed in the same category as dancers because of their training; plagiarism can be categorized as fraud.
• Compare/Contrast: Illustrate the similarities or differences between set topics, or introduce an outside idea to illuminate a difficult concept. Metaphors can be a powerful method for exploring or explaining. The circulatory system can be compared to geographical structure: it is like rivers but unlike lakes.
• Cause: Consider the cause or root of something. Was a car accident simply driver error? Or was it caused by fatigue? What about our society causes so many people to fall asleep behind the wheel? Do we live in a culture where exhaustion is promoted? Why?
• Effect: Discuss the effects of something. If obesity leads to disease, what does this suggest about policy, laws, or education? How can we avoid bad effects and replicate good ones?
• Evaluate: Determine whether something is good or bad, desirable or undesirable, ethical or unethical, effective or ineffective, etc. Or is it is somewhere in-between?
• Propose: Suggest a necessary action to take, or a solution for a problem.

As your research progresses, you can make the thesis stronger by developing your argument and analysis. You can use the following template to start:
In this essay, I plan to [argue/defend/analyze/demonstrate/explain] that _________, because (1) _____, (2)_____, and (3)_____.
When this format is applied to the working thesis in the previous example, it becomes:
Ex. In this essay, I plan to argue that the federal government should support public school voucher programs because (1) vouchers will improve public schools by forcing them to compete for students, (2) vouchers will ultimately cost tax-payers less money, and (3) vouchers will allow more students to get the superior education that studies show private schools provide.
 
Unless your assignment says otherwise, it’s not necessary to have a specific number of supporting reasons. This example has three, but you may have more or less depending on your argument.
As you work on your paper and build an introduction, the thesis or main idea can be reworded or refined.
Ex. While the use of school vouchers is currently decided by the states with no interaction or interference from the federal government, the country would be better served if the government would not only recommend but encourage the use of vouchers.
 
Notice the lines of argument are not articulated in that version of the thesis statement. If you want to map out the lines of argument you’ll be pursuing in the rest of the paper, you might prefer a thesis statement like this:
Ex. While the use of school vouchers is currently decided by the states with no interaction or interference from the federal government, the country would be better served if the government would not only recommend but encourage the use of vouchers. If more people used vouchers, public schools would be forced to improve to compete for students, taxpayers would ultimately save money, and more students would have access to a quality education.
 
Although you might want to express your thesis or main idea in a single sentence, it is not always necessary. You may define lines of reasoning earlier in the introduction, or break the thesis statement up into component parts. For longer papers, a thesis paragraph may even be appropriate.

Types of Thesis Statements

There are many types of effective thesis statements.
Ex. (advocate a course of action) The University should require incoming freshmen to take a physical education course.
Ex. (make comparisons and evaluate) Hitchcock was a more revolutionary filmmaker than Truffaut.
Ex. (attribute a cause) Much childhood obesity results from inferior cafeteria food.
 
Some thesis statements clearly map out the reasons supporting the thesis.
Ex. The United States should return to developing nuclear power because it is cheap, would reduce dependence on foreign sources of fuel, and is safer than other forms of energy.
 
Some thesis statements begin with an “although” clause, which establishes a contradiction that is then explored in the rest of the paper. An “although” thesis is especially helpful for building rapport with a hostile or skeptical audience because it allows you to find common ground.
Ex. Although the proposed health care reform legislation would improve access to health care for some select groups, it would ultimately fail to provide universal health care for all Americans.

Thesis Placement

In academic discourse, the thesis is typically presented at the end of the introduction. In some instances, however, you may find it more effective to withhold your thesis until the conclusion, which allows you to present evidence to soften potential resistance from your audience. You may also want to delay revealing your thesis in an informative speech to create suspense or build to a dramatic conclusion. If you choose to present your thesis at the end of an argument, be sure your audience is able to follow your line of reasoning.

Thesis Checklist

Be sure your thesis is:

• Specific and precise. “Vouchers are important to schools” is too vague to be useful.
• Arguable. “The Civil War was a crucial event in U.S. history” is too obvious to make a solid thesis.
• The right “size” for the assignment. “The American civil war is the defining event in our country’s history” is arguable, but probably too big to cover in a two-page paper.
• Suited to the assignment. Read back over the assignment prompt to make sure your thesis (and paper as a whole) address the right issue.
• Supported by the content of your paper. Read back over your supporting paragraphs and make sure they demonstrate what your thesis is arguing. If the paper has veered in an unexpected direction during the course of your writing process, revise your thesis to fit your evidence. It may help to write a summary sentence for each key piece of support and then compare those to your thesis statement.