Developing Effective Evidence

Evidence

Evidence is also referred to as support or facts. Evidence is just that: facts. Unlike claims, facts are indisputable. You may have heard the redundant phrase "true facts." The phrase is redundant because all facts are true: that's what makes them facts.

Evidence is what you use in persuasive writing to support the claims that you present.

Is it true that, in "Where I Lived, and What I Lived For," "Henry David Thoreau believed that preoccupation with insignificant events caused nineteenth-century Americans to overlook what is important in life"? The only way to find out is by examining the evidence. The evidence we should consider is easy to locate. We simply need to review Thoreau's essay and look for comments he makes that may support our claim. If we find such comments, these would be the facts we could use to support our interpretation.

Again, the evidence we use to argue such a claim falls under the category of "facts," things that are true and therefore cannot be argued or disputed. The easy way to see if you are presenting a statement of fact as evidence is to ask yourself if the statement is indisputably true. Is the statement below a fact and therefore possibly good evidence for a claim about Thoreau's essay?

• Thoreau says, "Men think that it is essential that the Nation have commerce, and export ice, and talk through a telegraph, and ride thirty miles an hour, without a doubt, whether they do or not; but whether we should live like baboons or like men, is a little uncertain."

Of course, this is a statement of fact. It is undoubtedly true that Thoreau made this comment in "Where I Lived, and What I Live For," so the sentence above might be good evidence to support a claim about Thoreau's essay. If someone questions if the sentence is true, the skeptic simply needs to open the book and read the passage. (But the quotation marks around the words above should make clear that these are Thoreau's actual words.)

Now, whether or not Thoreau's statement is a claim or a fact, whether people do or do not know if they should "live like baboons or like men," is irrelevant. Thoreau, in fact, is making a claim, but this is Thoreau's claim, not the claim of the writer using Thoreau's words as evidence. The fact that Thoreau made the comment, though, is indisputable.

All good arguments must be supported by a strong foundation of facts. An essay filled with claims but no supporting evidence is not really an argument at all. It is instead a collection of the writer's interpretations or beliefs, and readers will have no reason to believe the interpretations or beliefs is they are not well supported with facts.

How many facts do you need to support each claim that you make in a persuasive essay? Good question. To some extent, the amount of evidence you need depends on the claim you are trying to support. However, I think it's a good idea to present at least three facts to support each claim. One fact is almost never enough, and it's difficult to build a strong argument with only two facts. After all, I might be able to take one or even two statements that Thoreau makes and argue for all kinds of different meanings, ignoring the possibility that these meanings may not be suggested anywhere else in all of Thoreau's writings. Would you like someone drawing conclusions about beliefs you might have based upon only one statement you made at some point in your life?

Three facts seems to me the point when readers will start to be convinced that you have a well-supported interpretation. If you use at least three facts to support your interpretation of Thoreau's ideas, you are saying that Thoreau makes at least three different statements that all suggest the same thing to you, at least three statements that support your interpretation of Thoreau's beliefs. Could we draw a conclusion about some belief you may have based upon three statement you have made that suggest this belief? Well, we are more likely to be accurate than if we rely on only one statement to draw our conclusion.

Presenting Evidence

When you are using evidence to support your interpretation of a text, the evidence you take from the text itself can be presented in three different ways, outlined below.

1. A Quotation: When you quote from the text, you copy the words exactly as they appear in the original, and you put quotation marks around the words you take from the text. Quotation marks tell readers that what they see in your essay is exactly what they would see in the original text.

2. A Paraphrase: When you paraphrase, you put into your own words an idea that the writer conveys in the text. The paraphrase in itself should not convey any interpretation of the writer's ideas; instead, the paraphrase should be your own way of stating the exact idea that the writer conveys. In general, when you paraphrase, you use about the same number of words to convey the idea that the writer uses in the text. You should not put quotation marks around words you paraphrase, but you should make sure that you are conveying the same meaning that the writer conveys and that you really are using your own words to convey the idea.

3. A Summary: When you summarize, you use considerably fewer words to convey a writer's ideas. A writer might make a good point that you could use as evidence to support your interpretation of the text, but the writer might develop this idea over several paragraphs. You would not want to bring such a long quotation into your essay, nor would you probably want to devote a large section of your essay to paraphrasing everything that the writer says. Instead, you could reread the information from the text carefully and then summarize the writer's points, perhaps using only a few sentences to convey an idea that the writer develops in a page or more. Of course, you need to make sure that your summary is accurate, that it really does convey concisely the points that the writer develops. When you summarize, you should not put quotation marks around your own words.

In general, writers will use a combination of quotations, paraphrases, and summaries when developing an interpretation of a text. Again, only words copies exactly from the original should go in quotation marks in your essay. In some cases, you might use paraphrases and summarizes to put the writer's ideas into your own words, but you might include a few key words or phrases from the original as part of your paraphrase or summary. If this is the case, you need to make sure that those key words and phrases from the original are in quotation marks.

Warrants

Simply put, a warrant is the logical connection between a claim and a supporting fact. Sometimes, the logical connection, the way in which a fact logically supports a claim, will be clear, possibly so clear that no explanation from the writer is needed. More often, though, the writer needs to supply the warrant; in other words, the writer needs to explain how and why a particular piece of evidence is good support for a specific claim.

Look again at a claim and the one piece of supporting evidence for that claim I have mentioned so far as I discussed Thoreau's essay:

Claim:

Henry David Thoreau believed that preoccupation with insignificant events caused nineteenth-century Americans to overlook what is important in life.

Evidence:

Thoreau says, "Men think that it is essential that the Nation have commerce, and export ice, and talk through a telegraph, and ride thirty miles an hour, without a doubt, whether they do or not; but whether we should live like baboons or like men, is a little uncertain."

These two sentences could be the beginning of a paragraph. If so, what should my next sentence be? I suppose I could go on to present a second and then a third piece of supporting evidence for my claim, but am I sure that readers will be able to understand how the quotation I use is logically supporting my claim? I can assume that my readers are intelligent, so maybe they could figure out the connection, but I also should realize that, as the writer, it is my job to make sure everything in my essay is clear to readers. Therefore, I probably should supply some explanation as to how this quotation is supporting the claim, so my next sentence could be the following:

Warrant

The apparent preoccupation with external events, with the commerce and business of everyday life, may cause people to focus on what they are doing and not to look inward to examine how they are living.

As I wrote this warrant, I looked at two things: the claim I am making and the piece of evidence I am using to support that claim. In fact, my eyes were darting back and forth between the two statements as I was writing the warrant. With the warrant, I try to bring together the claim and evidence, demonstrating to readers how and why the evidence logically supports the claim. In this case, I have even used in my warrant a few words from the claim and from the evidence to help clarify the relationship. In the warrant, I use the word "preoccupied," recalling my claim, and the word "commerce," recalling the evidence. Notice as well that the phrase "how [people] are living" from my warrant recalls an important phrase from my claim, "what is important in life," and an important phrase from my evidence, "'whether we should live like baboons or like men." With the warrant, I should not simply paraphrase the claim or the evidence but instead demonstrate how the evidence supports the claim.

After I add this warrant to my slowly developing paragraph, I am then ready for the next sentence. Most likely, the next sentence will use another piece of supporting evidence from Thoreau's essay, followed by my explanation of how this evidence supports the claim. I will continue this pattern until I feel that I have established a strong argument for my claim.

Once I am finished with the paragraph, I am then ready to move on to the next paragraph. Most likely, I will repeat this same pattern with a different claim, but one related to my first claim. I will begin the body paragraph with a claim, followed by more supporting evidence and more explanation of how each piece of evidence supports my claim for that paragraph.

This page was last updated on Thursday, June 06, 2013. Copyright Randy Rambo, 2006.

USING EVIDENCE IN AN ARGUMENT

Does evidence speak for itself?

Absolutely not. After you introduce evidence into your writing, you must say why and how this evidence supports your argument. In other words, you have to explain the significance of the evidence and its function in your paper. What turns a fact or piece of information into evidence is the connection it has with a larger claim or argument: evidence is always evidence for or against something, and you have to make that link clear.

As writers, we sometimes assume that our readers already know what we are talking about; we may be wary of elaborating too much because we think the point is obvious. But readers can’t read our minds: although they may be familiar with many of the ideas we are discussing, they don’t know what we are trying to do with those ideas unless we indicate it through explanations, organization, transitions, and so forth. Try to spell out the connections that you were making in your mind when you chose your evidence, decided where to place it in your paper, and drew conclusions based on it. Remember, you can always cut prose from your paper later if you decide that you are stating the obvious.

Here are some questions you can ask yourself about a particular bit of evidence:

1. O.k., I’ve just stated this point, but so what? Why is it interesting? Why should anyone care?

2. What does this information imply?

3. What are the consequences of thinking this way or looking at a problem this way?

4. I’ve just described what something is like or how I see it, but why is it like that?

5. I’ve just said that something happens-so how does it happen? How does it come to be the way it is?

6. Why is this information important? Why does it matter?

7. How is this idea related to my thesis? What connections exist between them? Does it support my thesis? If so, how does it do that?

8. Can I give an example to illustrate this point?

Answering these questions may help you explain how your evidence is related to your overall argument.

HOW CAN I INCORPORATE EVIDENCE INTO MY PAPER?

There are many ways to present your evidence. Often, your evidence will be included as text in the body of your paper, as a quotation, paraphrase, or summary. Sometimes you might include graphs, charts, or tables; excerpts from an interview; or photographs or illustrations with accompanying captions.

Quotations

When you quote, you are reproducing another writer’s words exactly as they appear on the page. Here are some tips to help you decide when to use quotations:

1. Quote if you can’t say it any better and the author’s words are particularly brilliant, witty, edgy, distinctive, a good illustration of a point you’re making, or otherwise interesting.

2. Quote if you are using a particularly authoritative source and you need the author’s expertise to back up your point.

3. Quote if you are analyzing diction, tone, or a writer’s use of a specific word or phrase.

4. Quote if you are taking a position that relies on the reader’s understanding exactly what another writer says about the topic.

Be sure to introduce each quotation you use, and always cite your sources. See our handout on quotations for more details on when to quote and how to format quotations.

Like all pieces of evidence, a quotation can’t speak for itself. If you end a paragraph with a quotation, that may be a sign that you have neglected to discuss the importance of the quotation in terms of your argument. It’s important to avoid “plop quotations,” that is, quotations that are just dropped into your paper without any introduction, discussion, or follow-up.

Paraphrasing

When you paraphrase, you take a specific section of a text and put it into your own words. Putting it into your own words doesn’t mean just changing or rearranging a few of the author’s words: to paraphrase well and avoid plagiarism, try setting your source aside and restating the sentence or paragraph you have just read, as though you were describing it to another person. Paraphrasing is different than summary because a paraphrase focuses on a particular, fairly short bit of text (like a phrase, sentence, or paragraph). You’ll need to indicate when you are paraphrasing someone else’s text by citing your source correctly, just as you would with a quotation.

When might you want to paraphrase?

1. Paraphrase when you want to introduce a writer’s position, but his or her original words aren’t special enough to quote.

2. Paraphrase when you are supporting a particular point and need to draw on a certain place in a text that supports your point—for example, when one paragraph in a source is especially relevant.

3. Paraphrase when you want to present a writer’s view on a topic that differs from your position or that of another writer; you can then refute writer’s specific points in your own words after you paraphrase.

4. Paraphrase when you want to comment on a particular example that another writer uses.

5. Paraphrase when you need to present information that’s unlikely to be questioned.

Summary

When you summarize, you are offering an overview of an entire text, or at least a lengthy section of a text. Summary is useful when you are providing background information, grounding your own argument, or mentioning a source as a counter-argument. A summary is less nuanced than paraphrased material. It can be the most effective way to incorporate a large number of sources when you don’t have a lot of space. When you are summarizing someone else’s argument or ideas, be sure this is clear to the reader and cite your source appropriately.

Statistics, data, charts, graphs, photographs, illustrations

Sometimes the best evidence for your argument is a hard fact or visual representation of a fact. This type of evidence can be a solid backbone for your argument, but you still need to create context for your reader and draw the connections you want him or her to make. Remember that statistics, data, charts, graph, photographs, and illustrations are all open to interpretation. Guide the reader through the interpretation process. Again, always, cite the origin of your evidence if you didn’t produce the material you are using yourself.