Weighing a source's reliability
Judge how much weight a source can carry: who made it, when, for whom, and what they were in a position to know. Reliability is a question about one specific claim, not a label stuck on a whole document.
What a learner can do afterwards
- State who made a source, when, and for which audience, and say how each of those changes its weight
- Separate what a source is strong evidence for from what it is weak evidence for
- Explain why a one-sided source can still be good evidence of what its author wanted believed
- Say what would have to turn up for you to change your judgement about a source
1 · Read
You have compared sources and separated evidence from interpretation. Now ask how well a source supports a particular claim. Start with its maker, date and audience. Then ask what the maker could know. Someone nearby may have seen details that a distant writer missed. Someone writing much later may have used other records. These clues help you judge support; none guarantees accuracy.
A witness's letter says she saw a ship unload at the harbor. It also guesses why the ship's owner chose that route. Her reported observation gives more direct support for the unloading than for the owner's private reasons. Check her account against other evidence. Separate what she reports seeing from what she guesses. A useful source can contain both.
A one-sided public message can still help answer a question. A campaign leaflet praising a candidate shows the message its makers presented to voters. It does not establish that every promise was kept or every voter agreed. Its purpose is a clue about what the makers wanted readers to believe, not proof of every private thought.
Framing means choosing how to present an event. One report about a protest calls the crowd peaceful. Another calls it disorderly. Read beyond those words. Compare the actions each describes, the people each quotes and the evidence for each claim. Ask what is missing. Different wording can reveal different viewpoints, but it does not settle which factual account is accurate.
A fictional sourcing sentence says: 'The mayor's public leaflet urges residents to support the new park. It shows the message the mayor presented to residents, but it does not show that every resident agreed.' This answer links the maker, audience and purpose to a particular claim. Calling the leaflet biased would not explain those limits.
Name evidence that could change your judgment. If you doubt a claimed factory opening date, a dated inspection record or an independent report might help. Check that new evidence concerns the same factory and that its date and origin can be verified. Then reconsider your conclusion. You may revise it, become less certain, or keep it if the new evidence does not support a change.
In a fictional case, a supply record lists 60 coats ordered and 45 received. Read each entry and subtract: 60 minus 45 is 15. The record reports a shortfall of 15 coats. A commander's memoir blames an ally for a defeat. The shortfall does not by itself prove who caused it or whether it caused the defeat. Those claims need further evidence.
A source that supports one claim well may support another poorly. A builder's dated notebook may help establish when work began while offering little support for its guesses about what every resident thought. Explain the support and limits for each claim. Do not give every sentence the same weight because another sentence checked out.
Weigh each claim using the maker, date, audience, access to knowledge and other evidence. Explain its limits and what could change your judgment.
Original learning text and fictional examples authored for this dataset.
The four readings and accompanying flashcards were written for this dataset. The linked videos are credited to Khan Academy in the supplied source records; their publisher terms have not been verified.
2 · Watch
به انگلیسیTake it off screen
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.