The Writing Process: Background You’ll Need

  • Explain why using evidence is important for a strong argument

What is Evidence?

Have you ever heard the term “Exhibit A?”

In a trial, an exhibit is a piece of physical or documentary evidence shown to the jury — like a letter, photo, or document — to help prove a point. Exhibits are labeled Exhibit A, Exhibit B, Exhibit C, and so on, to keep them organized.

Jurors are instructed to base their decisions only on the evidence presented in the trial.[1]

Evidence in Academic Writing

When you read an academic article or essay, you are like the jury. The writer is making a claim and presenting evidence to convince you their claim is true. Think of each paragraph as its own “exhibit” — each one supports the larger argument of the essay.

  • Key sentence (topic sentence): States the main idea of the paragraph.
  • Supporting details (evidence): Provide examples, facts, or explanations that back up the key sentence.
A human pyramid with three people on the bottom, two in the middle, and one on top. The top person is labeled "Thesis", the middle two are labeled "Key Sentences of Paragraphs", and the bottom three are labeled "Supporting Details or Evidence in Paragraphs"
Figure 1. Just as the key sentences in the paragraphs support the overall thesis claim of the essay, the supporting details in each paragraph support the key sentence of the paragraph.

Just like in a trial, strong writing depends on strong evidence. Therefore, you want to gather your evidence first before deciding on your claim, so you can build a stronger, more supported argument.

How Evidence Builds an Argument

Imagine an argument like a pyramid:

  • The thesis (overall claim) is at the top.
  • The key sentences of each paragraph support the thesis.
  • The evidence in each paragraph supports the key sentences.

Evidence is the foundation — it holds the entire structure together. Without valid or credible evidence, the argument collapses.

Evidence in Different Disciplines

What is valid or credible evidence changes according to the academic discipline.

Evidence in the Humanities: Literature, Art, Film, Music, Philosophy

  • Scholarly essays that analyze original works
  • Details from an image, a film, or other work of art
  • Passages from a musical composition
  • Passages of text, including poetry

Evidence in the Humanities: History

  • Primary Sources (photos, letters, maps, official documents, etc.)
  • Other books or articles that interpret primary sources or other evidence.

Evidence in the Social Sciences: Psychology, Sociology, Political Science, Anthropology

  • Books or articles that interpret data and results from other people’s original experiments or studies.
  • Results from one’s own field research (including interviews, surveys, observations, etc.)
  • Data from one’s own experiments
  • Statistics derived from large studies

Evidence in the Sciences: Biology, Chemistry, Physics

  • Data from the author of the paper’s own experiments
  • Books or articles that interpret data and results from other people’s original experiments or studies.
It is important to remember that evidence NEVER speaks for itself. Any evidence used to support a position must be explained – the author of the text must prove that the evidence supports their thesis. 

  1. American Bar Association “How Courts Work” https://www.americanbar.org/groups/public_education/resources/law_related_education_network/how_courts_work/juryinstruct/ ↵