---
title: "Reading a Paper: the Claim, the Evidence and the Assumption"
description: "A research paper is read in a different order than it was written: the claim first, then the figure that carries it, then the method that produced the figure. The question that does the work is which "
canonical: https://lightmysky.com/learn/science/reading-a-paper-the-claim-the-evidence-and-the-assumption-mt_YFgMvbohC0
source: https://lightmysky.com/learn/science/reading-a-paper-the-claim-the-evidence-and-the-assumption-mt_YFgMvbohC0.md
retrieved: 2026-09-12
---

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# Reading a Paper: the Claim, the Evidence and the Assumption

A research paper is read in a different order than it was written: the claim first, then the figure that carries it, then the method that produced the figure. The question that does the work is which assumption would have to fail for the conclusion to collapse.

Subject: Science · Area: Scientific Inquiry · Ages 23 to 24
Page: https://lightmysky.com/learn/science/reading-a-paper-the-claim-the-evidence-and-the-assumption-mt_YFgMvbohC0

## Ready when they can

- Extracts the central claim and the single figure that supports it
- Identifies the assumptions the result depends on and how the authors tested them
- Judges whether the stated uncertainty supports the strength of the claim

## Lesson: Reading a paper backwards

Read a paper in the reverse of its writing: the claim first, then the figure that carries it, then the method that produced the figure. Your first job is separating the two parts of every argument: the claim, which the writers want you to believe, and the evidence, which they offer to convince you.

Evidence comes in types, each leaning on a hidden assumption. A study assumes the tested group was typical. A single striking example assumes one case can stand for many. A comparison assumes the two things were alike in every way that matters. An accepted fact assumes the background truly holds.

**Example.** The working question is: which assumption would have to fail for the conclusion to collapse, and did the authors test it. A study of an unusual group wobbles, an unfair comparison wobbles, and a lone example overgeneralizes. Also judge whether the stated uncertainty supports the strength of the claim.

**Tip.** Quasars show the habit in action. The far-away claim assumes redshift truly signals distance; without it the energy conclusion collapses. Doubters therefore hunted a mismatched pair: a quasar and a galaxy in nearly the same direction with very different redshifts. That is how you turn an assumption into a test.

**Recap.** Claim first, evidence sorted by type, assumptions hunted, and uncertainty weighed before trust.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Exploratory Analysis and an Honest Chart](https://lightmysky.com/learn/computing/exploratory-analysis-and-an-honest-chart-mt_Jpb78Z6Ytu)
- [Systematic Error, Controls and the Design of a Measurement](https://lightmysky.com/learn/science/systematic-error-controls-and-the-design-of-a-measurement-mt_rGjB_JcsLJ)

## Opens up

- [Writing Science: the Figure, the Error Bar and the Claim](https://lightmysky.com/learn/science/writing-science-the-figure-the-error-bar-and-the-claim-mt_uUQ4gKXTN0)