Eighth Grade · Reading · week 12

Evaluate Evidence Relevance

Assess whether the evidence in a persuasive argument is genuinely relevant and sufficient to support its claim, using Susan B. Anthony's 1873 voting-rights speech as a case study.

Not all evidence that sounds convincing actually supports the claim it is attached to. Evidence is relevant when it genuinely bears on the specific claim being made, and sufficient when there is enough of it to justify the size of the claim. A single anecdote might be relevant to a small claim but wildly insufficient for a sweeping one; a statistic might sound authoritative while actually measuring something slightly different from what the argument needs.

In 1873, Susan B. Anthony was tried for the "crime" of voting in the previous year's presidential election, and her speech defending herself is a tight, evidence-based argument. Her central claim: that denying women the vote is unconstitutional, not merely unfair. Her evidence: the Constitution's own preamble, which begins "We, the people of the United States," not "we, the white male citizens of the United States" -- and the Fourteenth Amendment, which defines a citizen as any person born in the United States, without specifying sex. Her reasoning connects the two directly: if women are citizens under the nation's own founding language, and the Constitution never actually restricts voting rights by sex, then laws blocking women from voting are the ones violating the Constitution -- not her vote.

📋 For the teacher
Teach it (10–15 min):
  • Look up the actual text of the Preamble together and read it slowly -- seeing "We, the people" in full context makes Anthony's argument click far faster than a summary can.
  • Practice the relevance test on a claim from daily life: state a claim your student cares about, then sort three pieces of "evidence" into relevant and not-quite-relevant piles.
  • Point out that being arrested for voting is itself part of the historical record, not just a detail -- the fact that this argument was made under literal legal indictment adds real stakes worth discussing.
  • Push past "that evidence sounds convincing" to "does that evidence actually address the specific claim being made" -- this is the single most useful move for evaluating any argument, in any subject.
Talk about it:
  • Why might a purely legal, textual argument be a stronger strategy for Anthony's specific 1873 trial than an emotional appeal about fairness would have been?
  • Can evidence be both true and irrelevant to a particular claim at the same time? Give an example.
  • Where else, outside of historical speeches, do you see people offering evidence that sounds convincing but does not actually match their specific claim?

Mastery looks like: They can distinguish evidence that is genuinely relevant to a specific claim from evidence that only sounds related, and can judge whether the evidence given is sufficient for the claim's size.

Common stumbles: Accepting evidence as support simply because it relates to the general topic rather than checking whether it addresses the EXACT claim; assuming more evidence is always better rather than weighing whether the evidence given actually fits.

See it visually

Interactive, spoken-aloud tools that show this idea in motion.

Persuasive AppealsBuild an argument with ethos, pathos, and logos.try →
Homework for this lessonType it, write it with a stylus, or print it for pencil & paper.open →
Records attendance + 15 min of Reading for this learner.
← Back to todayAll coursesYear planner