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Unit 2: Audience and the Thesis

Claims and Evidence: Writing

Turn a collection of evidence into a defensible thesis, and write paragraphs that pair each claim with evidence chosen to be strong and sufficient for it.

Topic 2.4 · 15 min read

It is tempting to pick a thesis first and then go looking for support. Strong writers often work the other way: they collect claims and evidence about an issue, sort them, and notice what the pile adds up to, and that becomes the thesis. A thesis built this way is one you can actually defend, because the evidence for it is already in your notes.

From a collection of evidence to a thesis

Before you have a position worth defending, you need material: facts, numbers, examples, things you've seen, things people have said. As you collect, write each item down as a separate note, and next to it, the claim it seems to support. Then:

  1. Sort the notes into groups that support the same point.
  2. Name each group's point in a sentence. Each of these will become a paragraph's claim.
  3. Ask what the groups add up to. The thesis is the one claim that all of them support together.
  4. Check the size. The thesis should claim as much as your evidence can support and no more. If one group is thin, either find more for it, narrow the thesis, or drop that point.
  5. Look at what doesn't fit. A note that argues against you is useful: it may show your thesis needs a limit ("except for lost items," "at least for first offenses").

This order protects you from a thesis that sounds good but that you can't support. It also gives you your paragraphs for free, since each group is one.

A thesis that needs defending

A thesis statement is the sentence or two that states your main claim. To work, it has to be something a reasonable reader could disagree with and something you can support with evidence. Facts don't qualify, because no one argues with them. Announcements of the topic don't qualify, because they claim nothing. Pure preferences don't qualify, because there is nothing to prove.

VersionProblem
School libraries have changed a lot in the last twenty years.A fact. Nothing to argue.
This essay will discuss whether school libraries should keep printed books.Announces the topic; takes no position.
There are good arguments on both sides of the printed-book question.Refuses to take a position.
I like printed books better than e-books.A preference about yourself, not a claim about the issue.
Printed books are better.A position, but too vague to defend: better for what, for whom?
School libraries should keep a printed collection, because students read longer texts more carefully on paper and because a shelf of books invites browsing in a way a search box does not.Takes a clear, arguable position on a specific question and gives the reasons the essay will defend.

The last version also previews the structure: a reader expects a paragraph about careful reading of long texts, then one about browsing, in that order. A preview helps the reader follow the argument and helps you stay on it. It is optional. A preview with a weak reason added just to make three ("and because books smell nice") hurts more than it helps, and some arguments are better previewed by the shape of the reasoning than by a list: "Although e-books are cheaper, a school that drops its printed collection saves money at the cost of the reading habits it exists to build." That thesis tells the reader the essay will grant the cost argument and then outweigh it.

A good thesis is also the right size. "Technology is changing reading" is too broad to defend in a forty-minute essay. "Our library should keep the copy of The Hobbit in room 104" is too narrow to be worth arguing. Aim for a claim you could defend in three or four solid paragraphs.

A paragraph built around a claim

Each body paragraph does one job: it defends one claim that moves the argument toward the thesis. Unit 1 introduced the parts; here is what each one has to do.

  • The claim. Usually the paragraph's first sentence. It is arguable, it is narrower than the thesis, and it is a step toward it. A summary of what's coming ("Newton is a famous scientist") is not a claim.
  • The evidence. Specific: names, numbers, dates, places, quoted words, things you saw. "Many people" and "studies show" are not specific. Topic 1.4 covers embedding quoted and paraphrased material in your own sentences.
  • The commentary. The sentences that say how the evidence supports the claim. Evidence does not explain itself. A reader who sees a statistic and no explanation has to guess what you think it proves, and graders don't guess for you. Unit 3 goes much further into commentary and the line of reasoning across paragraphs; for now, every piece of evidence gets at least one sentence that connects it to the claim.

Choosing the evidence is where Topic 2.3 comes in. Pick evidence that does the job your claim needs: a concrete case to illustrate, an analogy to clarify, a pattern to amplify. Pick evidence your audience will trust (Topic 2.2). And make it sufficient: if your claim is general ("unscheduled time helps people discover interests"), one example is a start but two very different examples, say one famous and one ordinary, show the claim holds across cases. If you only have one example, make the claim smaller to fit it.

Worked examples

Worked exampleFrom a pile of notes to a thesis

A student is writing to the board of the Brookfield Public Library, which is deciding whether to stop charging late fines. These are her notes (the library and its figures are invented for this example).

  1. Brookfield collected about $6,200 in late fines last year. The library's budget is $1.4 million.
  2. 1,150 cardholders can't borrow because they owe more than $10 in fines; the head librarian says most of them live in the two neighborhoods with the lowest incomes.
  3. Staff spend about five hours a week handling fine disputes at the desk.
  4. The town of Ashton dropped late fines three years ago. Its on-time return rate went from 91% to 89%, and about 300 people whose cards had been blocked came back in the first six months.
  5. A board member says fines teach responsibility.
  6. A parent at the board meeting said her children stopped going to the library after they ran up a $14 fine on picture books.
  7. The library lends laptops and hotspots, which are expensive to replace.
  8. The library's mission statement promises free and equal access for every resident.

Turn the notes into a thesis.

Show solution

Group the notes.

  • Fines shut out the people the library exists to serve: notes 2, 6, 8.
  • Fines barely change whether books come back: note 4 (the return rate moved two points), which also answers note 5.
  • Fines bring in little and cost staff time: notes 1 and 3. Six thousand dollars is less than half of one percent of the budget, and five hours a week of desk time is not free.
  • Doesn't fit: note 7. Expensive equipment that is never returned is a real loss.

Find what the groups add up to, sized to the evidence, with the limit note 7 demands.

Brookfield's library should stop charging late fines, because the fines keep out the residents its mission promises to serve, do little to bring materials back, and bring in little money for the desk time they take; the library should still charge to replace items that are lost.

Why this thesis works. A board member could reasonably dispute it (note 5 shows one already does), so it is arguable. Every part of it rests on a group of notes, so it is defensible. Its three reasons preview three paragraphs in a sensible order, starting with the strongest, which also ties the request to a value the board has already written down. And the last clause is note 7 at work: by keeping replacement charges, the student answers the most reasonable objection and claims only what the evidence supports.

A thesis the notes would not support: "Libraries everywhere should abolish all fees." The notes are about one library and late fines, and note 7 argues against "all fees."

A claim the notes would tempt you into: "cost nearly as much in staff time as they collect." It sounds sharper, but whether five hours a week of desk time is worth anything close to $6,200 a year depends on staff wages, which the notes don't give. The thesis says only what notes 1 and 3 prove: the fines are a sliver of the budget, and handling them takes staff time. To make the stronger claim, the student would first need the hourly cost of desk staff.

Worked exampleExam-style questions on a draft

The passage below is a draft of an essay a student wrote for the school newspaper.

(1) Every afternoon at 2:50, the halls of Westfield High empty out, and students who are falling behind in algebra go home with the same questions they had at noon. (2) Some of them could pay a private tutor, but at forty dollars an hour, most of them can't.

(3) The students who fall behind are often the ones too embarrassed to ask a teacher for help in front of a class. (4) A junior who passed the same course a year ago is less intimidating than a teacher, and she remembers exactly which steps confused her. (5) In a pilot run in two algebra classes last spring, the fourteen students who met with peer tutors twice a week raised their average quiz score from 64 to 77.

(6) Tutors would learn, too. (7) Explaining a step to someone else forces you to understand why it works, and not only how to do it.

(8) The program would cost the school almost nothing. (9) The library is open until 4:30 every day, and tutors would volunteer their time in exchange for the service hours every senior needs to graduate.

Question 1. The writer wants to add a sentence after sentence 2 that states the writer's position and previews the main points of the passage. Which of the following sentences best accomplishes this goal?

  • (A) Peer tutoring programs have been used in many schools.
  • (B) Westfield High should start a peer tutoring program, because it would help struggling students catch up, deepen the tutors' own understanding, and cost the school almost nothing.
  • (C) Should Westfield High start a peer tutoring program?
  • (D) Westfield High should start a peer tutoring program, because tutoring is a good way to help students.

Question 2. The writer wants to add a sentence after sentence 7 that provides evidence for the claim in sentence 6. Which of the following sentences best accomplishes this goal?

  • (A) In the same pilot, the eight juniors who served as tutors raised their own averages on the next unit test from 81 to 88, while classmates who did not tutor stayed at about the same level.
  • (B) The fourteen students who were tutored in the pilot said they felt more confident in class afterward.
  • (C) Many colleges look favorably on applicants who have tutored other students.
  • (D) Teaching is one of the most rewarding professions.
Show solution

1. (B). It states a position the writer could be challenged on and names the three points in the order the draft develops them: struggling students (sentences 3 to 5), tutors (6 and 7), cost (8 and 9). (D) also takes a position, and it is the tempting choice, but its reason is vague and previews none of the draft's points. (A) is a general fact, and (C) asks a question instead of answering it.

2. (A). Sentence 6 claims the tutors learn. Only (A) gives evidence about the tutors' learning, and it is strong evidence: a measured change, compared with students who didn't tutor. (B) is evidence about the students who were tutored, which supports paragraph 2's claim, not this one. (C) names a different benefit to tutors (college admissions), not learning. (D) is a general sentiment with no evidence in it.

The method. For a thesis question, list the draft's paragraph claims first and pick the choice that states a position and matches them. For an evidence question, reread the exact claim the stem points to and reject evidence that supports a neighboring claim.

Worked exampleWriting a body paragraph for an argument essay

Prompt: Some people argue that teenagers' schedules are now so full of organized activities that they have too little unstructured time. Take a position on how much unstructured time teenagers need, and defend it in an essay.

A student's thesis: Teenagers need unstructured time, because it is when they discover what interests them and when they learn to direct their own work, two things a schedule of organized activities can't teach.

Write the first body paragraph.

Show solution

Unstructured time is when people find out what they actually care about, because no one else has decided what the hour is for. In 1665, when plague closed Cambridge University, Isaac Newton went home to his family's farm in Lincolnshire for most of two years, with no lectures to attend and no one assigning him work. He spent that time on the questions that interested him, and he returned with early versions of his calculus, his experiments on light, and his first thinking about gravity. No course had required any of it. The same thing happens on a smaller scale to anyone given empty time. When my track season was canceled for a month after a storm damaged our field, I spent the first week bored and the next three taking apart a broken bicycle from our garage, watching repair videos, and rebuilding it; I now fix bikes for half my street. A coach's practice plan would have kept me busy and fit, but it would never have shown me that I like figuring out how machines work. Organized activities teach the skills someone else has chosen, and only unscheduled time leaves room to discover one nobody thought to offer.

Why this paragraph works.

  • The claim (first sentence) is the first reason in the thesis, stated as something a reader could dispute, with a reason attached.
  • The evidence is specific: a year, a place, a circumstance, and named results for Newton; a month, a cause, and an outcome for the student.
  • The evidence is sufficient for the claim. The claim is general, so the paragraph uses two very different cases. Newton alone would invite the reply "that's a genius, not a teenager"; the bicycle alone might be one lucky month. Together they suggest a pattern from the extraordinary to the everyday.
  • Commentary follows each piece of evidence. "No course had required any of it" says what the Newton example proves. The sentence about the coach's plan explains the bicycle story by contrasting it with what the organized alternative would have produced.
  • The last sentence ties back to the thesis by naming the contrast the whole essay is about: skills someone else chose versus skills you discover.

A weaker version might read: "Unstructured time is important. For example, Isaac Newton discovered gravity when he had free time. Also, I like to fix bikes in my free time. This shows that free time is good." Its claim is a vague evaluation, its evidence is thin (a half-remembered fact and an unexplained hobby), and its only commentary restates the claim. It would earn a low score for evidence and commentary even though it names the same two examples.

Where students lose points

On the exam

In the free-response section, the argument essay is scored on three things: a thesis that takes a defensible position on the prompt, evidence and commentary that support it, and the sophistication of the argument. The thesis can be more than one sentence, but keep it together in one place; the end of the introduction is the safest spot. It must answer the prompt's actual question, and a restatement of the prompt doesn't count. Evidence in the argument essay comes from what you know (reading, history, current events, experience), and specific evidence with commentary is what moves a response into the top scores for that row. The synthesis essay uses the same paragraph structure with the provided sources as evidence. In the multiple-choice section, draft questions ask which sentence best states the thesis or a paragraph's claim, and which evidence best supports a claim the stem names.

Check yourself

  1. Question 1

    A prompt asks students to argue their position on whether cities should ban cars from their downtown streets. Which thesis statement is defensible and previews the argument's structure?

    1. A

      Many cities around the world have experimented with car-free downtown streets.

    2. B

      Cities should ban cars from downtown streets, because removing traffic makes streets safer for pedestrians and brings more customers to local shops.

    3. C

      There are strong arguments both for and against banning cars from downtown streets.

    4. D

      Banning cars from downtown streets is an interesting idea that deserves discussion.

    Show answer

    B

    B takes a position a reader could dispute and names the two reasons the essay will develop, in order. C is the tempting choice because it sounds balanced, but it takes no position, so it can't be defended; A is a fact and D only comments on the topic.

  2. Question 2

    A student writes: "Social media makes teenagers less happy. My best friend deleted her accounts last month and says she feels better." Revise the claim so that the evidence is sufficient for it, without adding new evidence.

    Show answer

    A claim scaled to one case, for example: "Stepping away from social media can make a teenager happier, as it did for my best friend, who says she has felt better since deleting her accounts last month."

    One friend's experience can show that something is possible but not that it is true of teenagers in general. When you can't add evidence, shrink the claim until the evidence you have supports it.

  3. Question 3

    A body paragraph claims that a town's new bike lanes have made its downtown busier. It cites a count showing bicycle trips downtown rose from 300 to 900 a week after the lanes opened, then moves to the next paragraph. What is the paragraph missing?

    1. A

      A thesis statement

    2. B

      More statistics about bicycle trips

    3. C

      Commentary explaining how more bicycle trips show the downtown is busier, for instance by connecting riders to visits to shops and restaurants

    4. D

      A counterargument from someone who opposes bike lanes

    Show answer

    C

    The evidence shows more bike trips, but the claim is about a busier downtown, and the paragraph never connects the two; commentary is where that link is made. B is tempting, but more numbers of the same kind would still leave the connection unexplained.

  4. Question 4

    A student's notes on whether her school should allow phones at lunch fall into three groups: phones let students coordinate rides and after-school plans; students without phones at lunch talk to each other more, according to two teachers' observations; and the school already lets students use laptops at lunch. Two of the three groups support allowing phones. Write a thesis statement that the whole collection supports.

    Show answer

    One clear position that gives every group a place, usually by limiting the claim. For example: "The school should allow phones during the last ten minutes of lunch: that is enough time to arrange rides and after-school plans, it is consistent with the school's laptop rule, and keeping the rest of the period phone-free protects the conversation teachers see when phones are put away."

    A thesis built from a collection of evidence should be supported by all of it. A plain "allow phones at lunch" leaves the teachers' observations standing against the claim; limiting when phones are allowed turns those observations into support for the limit, so all three groups back the same thesis.

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