What is evidence? Review research and scholarship on the uses of evidence. Explore how evidence can help you communicate more clearly and persuasively. Learn to reason with evidence in workplace and academic writing.
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What is Evidence?

Evidence is

Just as detectives use various types of evidence to study crime scenes, writers, speakers, and knowledge workers . . . use different types of evidence to help their audiences better understand their claims, interpretations, point of view, and conclusions.

Related Concepts: Claim; Information, Data; Rhetorical Analysis; Rhetorical Reasoning

Evidence & the Writing Process

When you think of the term evidence, what comes to mind? CSILaw and OrderNCIS?

Certainly, detectives and law enforcement officers use evidence to prove that a criminal is guilty. What’s more, they use different types of evidence to find and convict the offending person(s), such as eyewitness accounts, DNA, fingerprints, and material evidence.

In order to identify the types of evidence you’ll need for any given occasion, you need to engage in rhetorical analysis of your communication situation.

You want to focus on audience because different readers, different discourse communities, have unique and sometimes conflicting ideas about what constitutes reliable evidence. For instance, some people may be easily swayed by their emotions. That’s why rhetoricians appeal to pathos rather than ethos and logos. Others may find such appeals to pathos to be inappropriate, unprofessional, deceitful.

Regardless of the type used, all evidence serves the same general function: evidence bolsters a writer’s claims. The trick is to determine, during composing, what type of evidence will most help your point.

Reasoning with Evidence

Evidence is the sine qua non of substantive academic and workplace writing. Educated readers are trained in critical literacy practices: they expect writers, speakers, knowledge makers . . . to support claims with evidence. They assess the validity of the evidence by questioning its currency, relevance, authority, accuracy, and purpose .

Academic culture is an evidence-based culture. Good scholarship requires claims supported by facts, theories, and research. Finding the evidence is not enough, though, as it needs to be successfully integrated into texts. When composers call on the ideas or authority of a book, article, web site, primary source, or other outside information, they should be practiced in choosing the best possible information and integrating it effectively into their own prose.  Research in composition and rhetoric reminds us that students struggling to understand new material often use sources in immature ways–perhaps by over-quoting  or patch-writing.

Audiences, discourse communities, have unique conventions for integrating evidence into texts and for citing paraphrases, summaries, and quotes from the texts of others. Thus, one of the first things you want to do when composing a text is find out what citation style the audience expects you to use.

  1. APA Style (6th Edition)
  2. CSE
  3. IEEE
  4. MLA Style and Formatting Guide (8th Edition)

Evidence as a Social, Cultural, Historical Artifact

Evidence is rooted in the epistemological assumptions that inform the interpretation and meaning-making processes of discourse communities.

Evidence vs Research

Students sometimes confuse evidence with research; the two do not mean the same thing.

Whereas evidence refers to a something that supports a claim, research is something much broader: it’s an effort to have a scholarly conversation about a topic.

Research begets evidence. Yet performing research should not just point you as a writer, speaker, knowledge maker . . . to useful quotes that you can use as support for claims in your writing

Research should tell you about a conversation, one that began before you decided upon your project topic. When you incorporate research into a paper, you are integrating and responding to previous claims about your topic made by other writers. As such, it’s important to try to understand the main argument each source in a particular conversation is making, and these main arguments (and ensuing subclaims) can then be used as evidence—as support for your claims—in your paper. Let’s say for a bibliographic essay you decide to write about the Indian Mutiny. Well, as the Indian Mutiny began around 1857, people have been writing about the Mutiny since that time. Thus, it’s important to realize that by writing about the Indian Mutiny now, you’re contributing to an ongoing conversation. By doing research, you can see what’s already been said about this topic, decide what specific approach to the topic might be original and insightful, and determine what ideas from other writers provide an opening for you to assert your own claims.

Ho, Hock Lai, “The Legal Concept of Evidence”The Stanford Encyclopedia of Philosophy (Winter 2015 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/win2015/entries/evidence-legal/>.

iFrame for a National Geographic snippet on Crime Scene Evidence