9 Thesis Statements, Topic Sentences, and Body Paragraphs

Thesis Statements

The thesis statement is the heart of any essay; it’s a concise statement (usually just one sentence) that summarizes the main point the author is making. If you think of an academic essay as presenting your perspective on a complex question, the thesis is your answer to that question, boiled down into a single statement. The rest of the essay will provide support for your answer and/or explain your answer in more detail, but a reader should be able to guess from your thesis more or less what to expect from the rest of the essay.

Arriving at a thesis statement can take various paths, but there are two common ones.

Path #1: You instinctively know what point you want to make.

In this situation, you may have a strong opinion or immediate response that you know you want to support in your essay. You will probably start with a broad, simple thesis statement that articulates that view. As you identify supporting points and possible counterarguments, you will almost certainly go back and refine that initial statement to be more specific.

Path #2: You aren’t sure what your main point is going to be.

In this situation, you may have a lot of opinions and thoughts you could share, but no single main idea is obvious. Alternatively, you have no clue at all what you might say in your essay. This situation is especially common when you are being asked to analyze something. Rather than starting with a thesis statement, you’ll work your way to a thesis statement by first figuring out what separate points you want to make and then articulating a single sentence that encapsulates or summarizes those points. In comparison to Path #1, you might not need to make as many changes to your thesis as you work, but you still may find that you change your mind as you draft!

Tension and Risk-Taking

A good thesis statement has some element of tension or riskiness to it. Remember, the issues we build academic essays around must be arguable. That doesn’t mean your thesis has to be a “hot take” on an issue, stating an outrageous or unsupportable opinion. Instead, you must strike a balance between being specific enough to be arguable while still being grounded in solid evidence and reasoning. The key is to advance a thoughtful interpretation or idea that readers may not have considered before. The potential for disagreement is what makes academic discourse meaningful. Be careful not to zoom so far out with your thesis statement that you end up with something like, “This issue has both pros and cons.” Even if you do discuss both pros and cons in your essay, you need to take a clear and specific stance. (What if you really can’t decide whether the pros or cons are more significant? Your thesis might be something like, “The pros and cons balance each other, making this issue impossible to decide.”)

Topic Sentences

If you derived your thesis statement by starting with the points you want to make in your essay, you already have a good idea of what your topic sentences will be. Topic sentences function like mini-thesis statements; each topic sentence sums up the point that you’re making in that particular body paragraph. The thesis statement, in turn, sums up and forecasts those topic sentences. A strong topic sentence tells the reader exactly what to expect from the paragraph, and has a clear relationship to the thesis statement. The reader should be able to tell that the topic sentence is developing a particular point that supports or explains the larger idea presented in the thesis statement.

Body Paragraphs

After the topic sentence, the body paragraph needs to contain both concrete evidence that supports the topic sentence, as well as your own explanation and justification of that evidence. Although there’s no set rule, a useful rule of thumb is that the paragraph should lean more on your explanation than on the evidence; a good ratio is about 2/3 your own explanations to 1/3 concrete evidence. Avoid opening or closing paragraphs with evidence. Instead, develop the habit of opening your body paragraphs with topic sentences and closing them with your own ideas that explain the evidence you have provided and make it clear how your point connects back to your thesis statement. One of the main reasons that students struggle to meet minimum word count requirements is that they don’t explain themselves fully, instead assuming that the evidence speaks for itself. In academic work, however, it’s important to always spell out exactly what you mean and why.

Example Thesis & Topic Sentences #1

The example thesis and topic sentences below are from a response essay written about the article “The Epidemic of Facelessness” by Stephen Marche. Note how the thesis incorporates two main ideas: emotional effectiveness and lack of logical persuasion. The topic sentences then detail those ideas more specifically.

Thesis: Marche’s article is emotionally effective, but not logically persuasive.

Topic Sentences:

• The specific examples Marche uses to illustrate trolling help readers feel emotionally invested in the issue.
• Marche’s word choices emphasize the seriousness of the problem.
• Marche makes unjustified logical leaps from what little research he cites.
• Marche fails to explore other possible causes for trolling.

Example Thesis & Topic Sentences #2

The example thesis and topic sentences below are from a synthesis essay responding to this assignment prompt: “How much do genetic versus environmental factors influence human behavior and mental health? Synthesize research findings from twin studies, adoption studies, and gene-environment interaction models.” Note how the order of ideas in the thesis statement is mirrored by the sequence of topic sentences.

Thesis: While both genetic and environmental factors significantly influence human behavior and mental health, aside from a few highly heritable conditions, most characteristics result from a complex interplay between genes and environment.

Topic Sentences:

• Twin and adoption studies have provided strong evidence for the strong heritability of a few conditions like schizophrenia, bipolar disorder, and autism spectrum disorder.
• Twin and adoption studies have also demonstrated that both genes and environment play a significant role in personality, as well as conditions like ADHD and depression.
• Gene-environment interaction models further show that a great many traits and conditions, including PTSD, phobias, substance use disorders, language, and obesity are strongly influenced by both genetics and environment.

Example Thesis & Topic Sentences #3

The example thesis and topic sentences below are from an evaluation argument essay.

Thesis: Despite its controversial nature, genetic engineering in agriculture is a good solution to global food security challenges.

Topic Sentences:

• Genetic engineering techniques can significantly enhance crop yields and nutritional content, addressing food scarcity in developing regions.
• The ability to create pest-resistant crops through genetic modification reduces the need for harmful pesticides, benefiting both farmers and the environment.
• The adoption of genetically modified crops can lead to increased farmer income in developing countries, contributing to economic stability and food security.
• Genetically modified crops can withstand extreme weather conditions, making them more resilient in the face of climate change.