Types of Evidence to Use in Writing and Essays

, Staff Writer
Updated May 22, 2020
Prove it thought while reading evidence essay
    Prove it thought while reading evidence essay
    Deagreez / iStock / Getty Images Plus

If you’re writing an essay, you can use various types of evidence to add supporting details and provide proof of your thesis statement. Knowing how to use these effectively and which types of evidence best support various points can help you write a stronger persuasive essay.

Six Types of Evidence in Writing

Think of your essay like a court case. The person reading your essay is the judge and jury; you need to convince the reader with good evidence in order to win. How you use this evidence in your work depends on what type of evidence it is. There are six main types of support in writing.

Anecdotal Evidence: Stories That Form a Connection

Many essays feature anecdotal evidence, especially as an attention-grabber or hook in the introduction. Anecdotal evidence is stories or case studies that support your thesis. On its own, it’s not a strong type of evidence because it’s the retelling of something that happened to one person or a few people. However, in writing, it helps you form a connection with your readers. That connection is very important if you want to convince readers of your thesis.

Some examples of anecdotal evidence include the following:

  • Interviews with someone who tells a story related to your thesis
  • A personal experience related to your topic
  • A case study from a journal or your own research
  • An excerpt from a journal or letter

Testimonial Evidence: Opinions of Experts

Just like in a court case, bringing in an expert opinion is a great way to add support for your writing. Their authority on the topic is frequently seen as above questioning. This is a good way to add support to your own opinions within an essay and to your thesis as a whole. You can also use testimonial evidence to support topic sentences in your paragraphs. You should always establish credibility for the expert before using that person’s opinion as supporting evidence in your essay.

Here are some examples of testimonial evidence you might use:

  • Direct interviews with experts in your topic
  • Quotes from an expert’s book, paper, or newspaper editorial
  • Conclusions from essays written by experts
  • Your own specialized knowledge if you have the credentials or experience to support it

Statistical Evidence: Numbers That Matter

Statistics are powerful, especially if they come from good sources. You can use statistics as a type of support in writing if they directly relate to your thesis. Especially shocking statistics can even capture your reader’s attention in your introduction and immediately begin to create support for your essay. The key is good sourcing, since statistics are easy to refute if they come from sources that are not reputable.

These are some examples of statistical evidence you might use in an essay:

  • Numbers gleaned from your own research or surveys you have conducted
  • Numbers from personal experience if you have sources to support them
  • Percentages from good sources like government reports or peer-reviewed studies
  • Measurements and numbers you gathered yourself or gathered from research

Textual Evidence: Support From Other Writing

If you are writing an essay about a book, speech, play, or other written document, you may need to use textual evidence to support your thesis. Whenever you use textual evidence, you need to be specific about where you found this evidence in the text. You should include page numbers and other information to guide the reader in verifying your evidence. You should also directly state why this evidence is important and what it proves.

Here are some textual evidence examples you might use in an essay:

  • Direct quotations from a book or other text source
  • Accurate summaries of what happened or was said in the text
  • Larger passages that relate directly to the thesis of your essay
  • Paraphrases of what the author says in the text

Analogical Evidence: Comparison With a Known Situation

One of the weakest types of evidence in writing, analogical evidence compares something that is not certain or known with a situation that is known. Then, the text draws conclusions based on that comparison. Although there are significant weaknesses in this type of evidence, it is sometimes the only option for offering support. To make this an effective type of support in writing, you need to make a strong case for the similarities between the situation about which you’re writing and the situation that is a known case.

These are some examples of analogical evidence you might use in your work:

  • A peer-reviewed study that is similar in many ways to the topic in your essay
  • An expert opinion about something very similar to your topic
  • A court case or historical event that is similar to your thesis
  • Statistics from a journal or direct research that is related to your topic but not exactly the same

Hypothetical Evidence: Enough Detail to Seem Real

Hypothetical evidence offers a projection or guess about a future scenario with enough sensory detail and imagery to feel like it is real. This is similar to an anecdote, but it is a weaker form of evidence. This story didn’t really happen, but your job is to make the reader believe that it could. Done well and used sparingly, this can form a connection with the reader. For example, if you are writing about why latchkey children should have supervision at home, you might imagine a situation in which an unsupervised child gets into trouble while cooking alone.

Here are some examples of hypothetical evidence:

  • A story about what would happen if your thesis were true
  • A story to go with a statistic from a good source
  • An imaginary event that would trigger an action related to your thesis

Use Evidence to Make a Strong Argument

Knowing how to use the different types of evidence is essential for any kind of persuasive writing, including essays. Each type of evidence has strengths and weaknesses, and how you use them depends on what you’re trying to prove. Consider mixing multiple forms of evidence in the supporting details for your essay to make the strongest argument.