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Put two sources beside each other: say what they both carry, what only one of them carries, and why a difference is usually not a disagreement.
Paper packet. Every task here also exists on screen, where it is checked automatically; answers written on paper are not assessed by Nydus. When you are back at a device, enter your answers there.
By the end of this lesson you can put two sources side by side and say what they both show, what only one of them shows, and what neither mentions. You will learn why a thing two sources both say is the surest thing you have, and why a difference between them hardly ever means somebody is lying.
Neither of the notes below is real. We wrote them both. They are about the made-up village of Ashfield and a fair that never happened. They are here so that you can practise asking what a source is evidence for, without being told anything untrue about the real past.
The fair was quieter than last year. I sold eleven pots of honey before noon and none after, because it rained. I never got to see the puppet show.
Bel keeps the shop. She wrote this at the end of the day, in the book where she writes down what she has sold.
The best part of the fair was the puppet show. It was crowded all the way round the stage. I got soaked running home.
Tomás is nine. He wrote this in his own notebook that evening, because he wanted to remember the day.
The two notes do not disagree with each other. Bel never saw the puppet show, so she says nothing about it. Tomás was standing right in front of it, so he can tell you it was crowded — but he was not in the shop, so he cannot tell you how much honey was sold. Each note is strong evidence for what the person writing it was near, and weak evidence for everything else. And both of them noticed the rain.
You can say what one source states, who made it and why, and how far it reaches. Every one of those questions is about a single source. This lesson is the first one about two.
Two sources agree when both say the same thing, and disagree when one denies what the other says. A source is silent about everything it never mentions, which is neither. When two sources that did not copy each other both say a thing, it is backed up.
Bel and Tomás were at the same made-up fair. Bel was behind her counter all afternoon; Tomás was standing in front of the puppet stage. Their two notes are not the same, and that is where the useful part is.
Start with what they both say. Bel writes that it rained. Tomás writes that he got soaked running home. Neither was copying the other, so the rain is the surest thing in the whole afternoon. That is what two sources buy you.
Now the differences. Bel says nothing about the puppet stage. That is not her saying the stage was empty; it is her saying nothing, because she never saw it. Before you decide two sources disagree, ask the smaller question first: were they even looking at the same thing?
Another way: picture
Two torches shining on a dark wall. Each lights a circle, and the two circles overlap a little. What you see best is in the overlap; what one torch alone reaches you see less well; what neither reaches you cannot see at all.
Another way: steps
One: what do both sources say? Two: what does only the first one say? Three: what does only the second one say? Four: is anything actually denied by the other, or is it only missing?
Only the last of these is a real disagreement, and it is the rarest.
| What you see | What it usually means | Example |
|---|---|---|
| One mentions it, the other says nothing | They were in different places, or doing different jobs | Bel never saw the puppet stage |
| Both mention it and say the same | You can be surer of it than of anything either says alone | Both of them noticed the rain |
| One says yes and the other says no | One of them is mistaken, or they mean different things | A cart that went out and did not stop at the shop |
The commonest mistake is reading silence as a no: Bel not mentioning the puppet show does not mean there was none. The second is deciding a difference means somebody is lying, when almost always it means somebody was somewhere else. The third is giving up on both sources at the first difference.
Bel writes that it rained. Tomás writes that he got soaked running home.
Two different sentences, one fact underneath them.
Neither of them read the other's note, so nobody copied anybody.
That is what makes the agreement worth something.
So the rain is the surest thing we have about that afternoon.
Two separate sources beat one source every time.
Tomás says the stage was crowded. Bel's note does not mention the stage at all.
Look for the denial before you call it a disagreement.
There is none. Bel says she never got to see the show.
She could not have written about a stage she never reached.
So the two notes are silent and not opposed, and Tomás's note is the only evidence either way.
Silence leaves the question to whoever was there.
A made-up list of what the Ashfield cart carried, and Bel's made-up note from the same Friday. First source, the cart list: "Friday: flour and 6 baskets of apples to the market. Home again before dark." Second source, Bel's note: "The cart went out on Friday but brought nothing for the shop. I waited until dark." Match each of these three things to where you could find it.
| Only the first source shows this. | Only the second source shows this. | Both sources show this, so it is the surest of the three. | |
|---|---|---|---|
| Six baskets of apples went to the market. | |||
| Bel waited in the shop until it got dark. | |||
| The cart went out on Friday. |
The two made-up notes about the Ashfield fair are at the top of this lesson. Three questions about them, one after another.
This task has no paper form; do it on a device.
Ana wrote in the made-up register: "Thursday: 11 children in the room. 3 children away. The stove smoked all morning." Ravi wrote in his made-up diary: "The room was freezing on Thursday. We read the story about the river." Fill in the table. For each question, does that source say yes, say no, or say nothing about it at all?
| Question | The first source | The second source |
|---|---|---|
| Were some children away? | ||
| Did the stove smoke? | ||
| Was the room cold? |
A made-up cart list says the cart went to the market on Friday. Bel's made-up note says the cart brought nothing for the shop that day. What is the likeliest reason for the difference?
Neither of these two sources is old, and they are both about the same day. Mark the one thing that *both* of them show.
This task has no paper form; do it on a device.
Lesson test: one question per skill, one attempt each, no hints. Your answers are checked when you submit.
A made-up Ashfield register for Thursday, and a made-up diary kept by a child in the same room. First source, the register: "Thursday: 11 children in the room. 3 children away. The stove smoked all morning." Second source, Ravi's diary: "The stove smoked so much on Thursday that my eyes stung. We read the story about the river." Match each of these three things to where you could find it.
| Only the first source shows this. | Only the second source shows this. | Both sources show this, so it is the surest of the three. | |
|---|---|---|---|
| Three children were away that Thursday. | |||
| The story about the river was read that day. | |||
| The stove was smoking. |
You can say what two sources agree on, what only one of them carries, and when a difference between them is silence rather than disagreement. Next time two people tell you about the same afternoon, listen for the part they both mention.