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One case, confidence, popularity and a famous name can sound strong while giving little support.
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.
You will spot four kinds of reason that sound stronger than they are — one case stretched, only confidence, only popularity, and a famous name who knows nothing about the question — and ask the question that would test each one, without deciding the claim must be false.
You can weigh reasons with three questions: this very case? checkable? many cases? Some reasons fail those questions while sounding very strong. This lesson names four of them.
| Term | What it means |
|---|---|
| This lesson's terms | A reason settles a claim when it leaves a careful listener with little room to doubt it. A reason starts a question when it makes the claim worth looking into without settling it. Popularity is how many people believe something; confidence is how sure someone sounds. |
| Supported conclusion | The conclusion the stated reasons reach, including the limits on its group, time or conditions. |
1. One case, stretched. This beach is always packed: it was packed when we went in August. One August day is real, and the claim is about every day. Ask: how many times?
2. Only confidence. The café shuts at four. I'm a hundred percent sure. How sure someone feels is a fact about them, not about the café. Ask: how do you know?
3. Only popularity. The old well grants wishes — everyone round here says so. Lots of people believing something does not make it true. Ask: has anyone checked? (Watch the exception: if the claim is about what people think — most people want a crossing — then counting people is exactly the right evidence.)
4. A famous name who knows nothing about it. A famous violinist bought this soccer. She knows about music, not soccer balls. Ask: how would they know about this?
None of these makes a claim false. The café might shut at four and the beach might be packed again. A weak reason starts a question without settling it, and the careful response is to ask the question that would settle it, not to throw the claim away.
Another way: picture
A weak reason is like a signpost that says treasure this way. It is worth following to look. It is not the treasure.
Another way: questions
One question for each:
A weak reason may sound lively, confident or impressive. None of those sounds tells you how well it supports the claim. 'Everyone knows' hides the question of who knows and how. 'A famous player uses it' may tell you about that player's choice without telling you whether the thing suits your task. Ask what information reaches the claim after the impressive words have been removed.
Do not replace one shortcut with another. A famous person can give a good reason. A popular idea can be correct. The mistake is treating fame or popularity as enough by itself for a different claim. If a player explains that a shoe fits their injured foot, that is evidence about their experience. It is not proof that the shoe is best for every child's foot.
One case can show that something happened once. It cannot usually show how often it happens. 'My bean plant grew without water yesterday' does not show that bean plants never need water. There may have been moisture in the soil already. Ask which words in the claim stretch beyond the one case: all, always, never and guaranteed deserve attention.
When you spot a weakness, name a useful next check. Instead of saying only 'bad reason', ask for a comparison, a count, a source or an explanation of the link. This turns criticism into a route forward. You are examining the support rather than trying to win by making the speaker look foolish.
The old mill is haunted. Nearly everyone in the village says so. The reason sounds convincing. What is it really made of?
The supported answer is: Only how many people believe it.
The distinction in this case is that lots of people saying something does not make it true when the claim is about the mill, not about what people say.
The shortcut through the woods is quicker. Trust me, it obviously is. The reason sounds convincing. What is it really made of?
The supported answer is: Only how sure the speaker sounds.
The distinction in this case is that trust me and obviously only tell you the speaker is confident; nothing has been timed.
These hiking boots are the most waterproof you can buy. A famous chess champion wears them. The reason sounds convincing. What is it really made of?
The supported answer is: A famous person who knows nothing special about this.
The distinction in this case is that a chess champion's fame is about chess, not about testing boots in water.
It always rains on the day of the village fair. It rained on the day of the fair last year. The reason sounds convincing. What is it really made of?
The supported answer is: One single case, stretched to cover every case.
The distinction in this case is that last year is one fair day, and the claim is about all of them.
Our cat hates every dog in the world. He hissed at the dog next door on Sunday. The reason sounds convincing. What is it really made of?
The supported answer is: One single case, stretched to cover every case.
The distinction in this case is that one hiss at one dog is a single case, and the claim is about every dog.
The ice on the pond is definitely safe. I'm completely, totally sure about it. The reason sounds convincing. What is it really made of?
The supported answer is: Only how sure the speaker sounds.
The distinction in this case is that being very sure is a fact about the speaker; it tells you nothing about the ice.
This cough mixture works better than any other. A famous pop singer says she uses it. The reason sounds convincing. What is it really made of?
The supported answer is: A famous person who knows nothing special about this.
The distinction in this case is that a singer knows about singing; being famous gives her no special knowledge of cough mixtures.
Carrots let you see in the dark. Everybody knows that. The reason sounds convincing. What is it really made of?
The supported answer is: Only how many people believe it.
The distinction in this case is that everybody knows counts believers, and a claim about eyes is not settled by counting believers.
Four weak reasons. Match each one to the question that tests it best.
The shortcut floods — it happened to my cousin once. / The shop shuts at five. I'm absolutely sure. / The lake has a monster in it. Everybody says so. / This glue is the strongest. A famous footballer uses it. / How many times has it actually happened? / How do you know? Did you see the sign? / Has anyone actually checked? / How would a footballer know about glue?
It happened to my cousin once is one story, so ask how many times it has happened. I'm absolutely sure is confidence, so ask how the speaker knows. Everybody says so counts believers, so ask whether anyone has checked; a famous footballer uses it needs how would a footballer know about glue?
A toothpaste advert. Mark every sentence that sounds like support for buy Sparkle but gives none worth trusting.
Sparkle is obviously the best toothpaste there is. / Everybody's switching to Sparkle! / Racing driver Max Volt brushes with Sparkle every day. / In a dentist's test of 200 people, Sparkle removed more stains than two other brands. / Sparkle comes in a bright blue tube.
Obviously the best is only confidence, and everybody's switching is only popularity. A racing driver is famous for driving, not for knowing about teeth. The dentist's test of 200 people is a count someone could check, so it is real support and stays unmarked. The blue tube does not sound like support at all.
A local newspaper headline says: Fryer's is the best chip shop in the country, say its regular customers. What is the weakness in this support?
The supported answer is: Only people who already choose Fryer's were asked, and nobody compared it with other shops.
The claim is about every chip shop in the country. The people asked are Fryer's own regulars. They already chose Fryer's, and none of them was asked to compare it with shops elsewhere. So their view is real and it covers too little. It is popularity among the people least likely to disagree.
An advertisement says, 'Our puzzle book makes every child brilliant. A famous singer owns it. One student finished a page in two minutes. Thousands of copies have been sold.' The large claim concerns every child and a very broad improvement. The three supporting statements do not measure that improvement.
Owning the book tells us nothing about whether the singer used it, liked it or improved through it. A student completing one page tells us about one student and one page. We do not know the page's difficulty or how quickly that student worked before using the book. Sales count purchases, not learning. Each sentence may be true while the advertised conclusion remains much larger than the evidence.
Separate questions that the facts could answer. The sales figure could help answer whether the book is widely bought. The two-minute result could show that at least one student completed that page quickly. Neither proves a change in every child's ability. Keeping these smaller claims allows us to use the information without stretching it.
For the learning claim, a better check would define an actual skill, compare similar tasks before and after practice, and include more than one learner. Even that would not establish that every child becomes brilliant at everything. A sensible classroom reply is, 'These facts do not yet show the promised improvement. What was tested, and what changed?' We are not deciding whether the book is fun or whether the singer is trustworthy. We are testing the precise support for the precise promise.
Thinking a weak reason makes the claim false. It only means the claim is not settled yet.
Thinking one case never settles anything. There are frogs in the pond is settled by one frog. One case is weak only for a claim about many cases.
Calling every count of people popularity. A survey is the right evidence for a claim about what people want.
Calling a weak reason irrelevant. One packed day at the beach is about the beach. It is relevant and too small.
The quickest way to the station is along the canal. Believe me, it's obvious.
The quickest way to the station is along the canal. Believe me, it's obvious.
Find the reason.
State the result of this reading move.
Find the reason.
This records the link just identified: The quickest way to the station is along the canal. Believe me, it's obvious.
The only reason is believe me, it's obvious: the speaker's confidence.
The only reason is believe me, it's obvious: the speaker's confidence.
Nothing has been timed or measured.
State the result of this reading move.
Nothing has been timed or measured.
This records the link just identified: The only reason is believe me, it's obvious: the speaker's confidence.
The question that would settle it: have you timed both ways? A stopwatch beats a believe me.
The question that would settle it: have you timed both ways? A stopwatch beats a believe me.
Ask the question; do not just reject the claim.
This sun cream works best. A famous pianist uses it.
This sun cream works best. A famous pianist uses it.
The reason is a famous name.
State the result of this reading move.
The reason is a famous name.
This records the link just identified: This sun cream works best. A famous pianist uses it.
Ask how would a pianist know about sun cream? His fame is for music.
Ask how would a pianist know about sun cream? His fame is for music.
His name gives the sun cream no support.
State the result of this reading move.
His name gives the sun cream no support.
This records the link just identified: Ask how would a pianist know about sun cream? His fame is for music.
Compare: a skin doctor tested five sun creams on the same beach, and this one blocked the most sun. That one could settle it.
Compare: a skin doctor tested five sun creams on the same beach, and this one blocked the most sun. That one could settle it.
The difference is knowing about this question.
Identify the task before answering its parts.
Pens observed: {{b0}}
Days observed: {{b1}}
Pens not observed: {{b2}}
The three labeled spaces ask for different parts of this analysis, so keep their order visible.
Locate the evidence for the first part.
Only one pen's performance is supplied, although the promise covers the entire set.
This is the supplied information that bears on work out pens observed.
Work out pens observed.
1
Only one pen's performance is supplied, although the promise covers the entire set.
Work out days observed.
1
Yesterday provides one day of observation, not a full year.
Work out pens not observed.
7
The remaining 7 pens have no observations here; neither the group nor the time supports the broad promise.
Write the completed analysis in its original order.
1 / 1 / 7
Read these entries with their labels: Work out pens observed. / Work out days observed. / Work out pens not observed.
Swallowed chewing gum stays in your tummy for seven years. Everybody knows that. What is the reason made of?
Swallowed chewing gum stays in your tummy for seven years. Everybody knows that. What is the reason made of?
It counts believers: that is popularity.
Which question tests it?
Does the weak reason make the claim false, or unsettled?
Each claim below comes with one single case as its reason. Say whether the case settles the claim, or only starts the question. Use these category identifiers: A = settles the claim; B = only starts the question. Select the identifier, not the category's words.
| What does the one case do? | |
|---|---|
| Our cat hates every dog. — He hissed at the neighbor's dog on Sunday. | |
| The corner shop sells bread. — I bought a loaf there this morning. | |
| It always rains on the day of the fair. — It rained on the day of the fair last year. | |
| There are frogs in the pond. — I saw three frogs in it today. |
An advert says every one of 11 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Work out pens observed.
b0
Count actual observations rather than promises.
Work out days observed.
b1
Distinguish the observation period from the promised period.
Work out pens not observed.
b2
Subtract the observed objects from the advertised group.
An advert says every one of 15 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Pens observed: b0
Days observed: b1
Pens not observed: b2
An advert says every one of 9 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Pens observed: b0
Days observed: b1
Pens not observed: b2
An advert says every one of 10 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Pens observed: b0
Days observed: b1
Pens not observed: b2
An advert says every one of 13 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Pens observed: b0
Days observed: b1
Pens not observed: b2
Lesson test: one question per skill, one attempt each, no hints. Your answers are checked when you submit.
An advert says every one of 12 new pens lasts a year. Its only evidence is that one pen worked yesterday. Write the number of pens actually observed, the number of days observed, and the number of the advertised pens not observed.
Pens observed: b0
Days observed: b1
Pens not observed: b2
You can say what a weak reason is made of and which question would test it. Say why it was packed in August starts a question about the beach is always packed without settling it. Next: when two people disagree, and nobody is lying.
15. Your turn: the chewing gum, step 2
Which question tests it?
A weak reason starts a question; it does not settle it.
15. Your turn: the chewing gum, step 3
Does the weak reason make the claim false, or unsettled?
A weak reason starts a question; it does not settle it.