to the top

#2 - A large number of drivers routinely violate highway

linda.an
LSAT Apprentice
 
Posts: 9
Joined: Wed Jun 08, 2016 11:21 pm
Points: 0

Hello,

Please explain why answer D) need to be eliminated.

Trying to negate answer D) gives me that "most drivers who exceed the speed limit do so intentionally". Therefore, even if devices are installed in their cars, they would ignore them because they intentionally exceed the speed limits. Wouldn't such negation prove conclusion false?

Thank you!
Clay Cooper
PowerScore Staff
PowerScore Staff
 
Posts: 243
Joined: Fri Jul 03, 2015 3:30 pm
Points: 103

Hi linda.an,

Thanks for your question.

I think you have misunderstood what the device does; you mention that the negated form of D suggests to you that the drivers (who speed intentionally) would just ignore it. However, the stimulus states that the device would actually prevent speeding. In other words, the drivers couldn't ignore it.

In reality, the negated form of answer choice D has no impact on the argument - whether or not drivers who currently speed do so intentionally does not really have any bearing on whether a device which could automatically prevent them from speeding might reduce the overall number of accidents.

Does that clarify it somewhat?
Sophia123
LSAT Leader
 
Posts: 44
Joined: Mon Mar 20, 2017 11:43 am
Points: 44

Hi,

I am confused on why answer choice E should be eliminated. If negated it would read "If the fines for speed-limit violations were increased, the number of such violations would be reduced" I thought this would weaken the argument that devices need to be installed since there is another way to reduce these accidents.

I tried to think through why this might be wrong, and all I can think of is that drivers might still choose to ignore the increased fine and will still speed thus the number of accidents would not decrease, which would not weaken the argument. Is this rationale correct?

Thank you in advance!

-Sophia
Francis O'Rourke
PowerScore Staff
PowerScore Staff
 
Posts: 474
Joined: Fri Mar 10, 2017 2:44 pm
Points: 469

Hi Sophia,

It looks like you are assuming a lot more about the speaker's position than is given to us. The speaker's argument is not that we need to install these devices because there is no other way to lower accident rates. The argument only claims that installing the devices would prevent most accidents. Put another way, the speaker cares only about whether this device is effective or not. Whether or not fines would reduce accident rates does not change whether the device would prevent most accidents.
Jerrymakehabit
LSAT Leader
 
Posts: 40
Joined: Mon Jan 28, 2019 11:54 pm
Points: 40

Can someone please help me with (E)?

I think (E) could be an assumption. "installing devices in all cars...would prevent most accidents". To me, it is a causal relationship that installing devices in all cars... :arrow: prevent most accidents. (E) works as a defender that eliminating alternative cause "fines for speed-limiting violations were increased". LR Bible 2019 talks about this on page 366. So "fines for speed-limiting violations were increased" can not cause "prevent most accidents". The author assumes any idea that would weaken the argument is impossible and cannot occur. So (E) seems right.

Thanks
Jerry
James Finch
PowerScore Staff
PowerScore Staff
 
Posts: 603
Joined: Wed Sep 06, 2017 5:06 pm
Points: 600

Hi Jerry,

While it's true that the stimulus, and thus the correct answer choice, is trying to make forcing people to drive no faster than the speed limit a cause of the effect of preventing most accidents, it's not making the claim that installing a limiting device is the only way to do this. Instead, it is claiming that the limiting device is one effective way to do this; whether there are others or not is irrelevant to the argument. So the assumption we need will help show that a limiter is an effective way to prevent most car accidents.

(C) does this by avoiding a possible complicating factor, the need for exceeding the speed limit in emergencies in order to avoid accidents. As long as that need doesn't exist, then the conclusion still could work.

(E) fails to be necessary to the conclusion because it brings in another potential way to reduce speeds, but the original argument doesn't care about alternatives, it just wants to show that the limiter is effective at preventing accidents. Other ways, like fines, may also be effective, but this has no bearing on the argument in the stimulus.

Hope this clears things up!
Jerrymakehabit
LSAT Leader
 
Posts: 40
Joined: Mon Jan 28, 2019 11:54 pm
Points: 40

James Finch wrote:Hi Jerry,

While it's true that the stimulus, and thus the correct answer choice, is trying to make forcing people to drive no faster than the speed limit a cause of the effect of preventing most accidents, it's not making the claim that installing a limiting device is the only way to do this. Instead, it is claiming that the limiting device is one effective way to do this; whether there are others or not is irrelevant to the argument. So the assumption we need will help show that a limiter is an effective way to prevent most car accidents.

(C) does this by avoiding a possible complicating factor, the need for exceeding the speed limit in emergencies in order to avoid accidents. As long as that need doesn't exist, then the conclusion still could work.

(E) fails to be necessary to the conclusion because it brings in another potential way to reduce speeds, but the original argument doesn't care about alternatives, it just wants to show that the limiter is effective at preventing accidents. Other ways, like fines, may also be effective, but this has no bearing on the argument in the stimulus.

Hope this clears things up!


Hi James,

Thanks for the explanation. I totally understand why C is correct. But meanwhile I feel E could be correct too. Can you please tell where is wrong in my analysis above regarding E? Is it because E is going too far away from "installing devices in all cars.."?

"I think (E) could be an assumption. "installing devices in all cars...would prevent most accidents". To me, it is a causal relationship that installing devices in all cars... :arrow: prevent most accidents. (E) works as a defender that eliminating alternative cause "fines for speed-limiting violations were increased". LR Bible 2019 talks about this on page 366. So "fines for speed-limiting violations were increased" can not cause "prevent most accidents". The author assumes any idea that would weaken the argument is impossible and cannot occur. So (E) seems right."
Brook Miscoski
PowerScore Staff
PowerScore Staff
 
Posts: 226
Joined: Thu Sep 13, 2018 6:38 am
Points: 226

Jerry,

The reason that (E) is not an assumption is that the argument is concerned with the claim that installing governors is one way of preventing most accidents. It doesn't matter if there is another way of preventing accidents, because the stimulus doesn't claim that installing governors is the only way or even the best way.

Another way that you can see that (E) is not an assumption is the negation technique. Negated, (E) says "increasing fines would reduce speeding violations." Okay, so what? That does not prove that installing governors wouldn't work. (E) is not an assumption.

This scenario will repeat itself, so you will need to learn to look for whether the stimulus is claiming something is a possible solution or whether the stimulus is claiming that something is the only solution.
Jerrymakehabit
LSAT Leader
 
Posts: 40
Joined: Mon Jan 28, 2019 11:54 pm
Points: 40

Brook Miscoski wrote:Jerry,

The reason that (E) is not an assumption is that the argument is concerned with the claim that installing governors is one way of preventing most accidents. It doesn't matter if there is another way of preventing accidents, because the stimulus doesn't claim that installing governors is the only way or even the best way.

Another way that you can see that (E) is not an assumption is the negation technique. Negated, (E) says "increasing fines would reduce speeding violations." Okay, so what? That does not prove that installing governors wouldn't work. (E) is not an assumption.

This scenario will repeat itself, so you will need to learn to look for whether the stimulus is claiming something is a possible solution or whether the stimulus is claiming that something is the only solution.


Hi Brook,

Thank you for your explanations. How exactly can you tell "because the stimulus doesn't claim that installing governors is the only way or even the best way"?

The stimulus says "installing devices ... would prevent most accidents". On page 287 of the 2019 LR Bible, "the central assumption of basic causal conclusions" indicates the "only cause" theory. Would this seem contradicting with your explain?

Thank you
Jerry
Robert Carroll
PowerScore Staff
PowerScore Staff
 
Posts: 487
Joined: Fri Dec 06, 2013 7:18 am
Points: 423

Jerry,

Note that the author is talking about a situation that isn't real yet - the author wants things changed so that the devices will reduce accidents. In that situation, the author would claim that the device reduced accidents. But that situation hasn't happened yet. What if the device were not installed, but speeding fines were increased? I don't know what the author would say about such a situation, because it's NOT the situation where the device has been installed. The author is positing a certain cause/effect relationship in one case. The author isn't describing a situation that already exists and is not trying to claim that other methods would be ineffective. So there's no conflict between Brook's point above and the "only cause" language of the Logical Reasoning Bible.

Think of it this way. We install the devices. The author would then say "OK, accidents will be reduced by the devices, and only by the devices." The author will say the former because the author thinks the devices would be effective, and the latter depends on the "only cause" logic of causation. If instead fines were increased and the device was not installed, the author wouldn't say "Accidents will be reduced by the device" (because the device isn't even installed here), or "Accidents won't be reduced at all" (the author's argument is an argument only about situations where the device has been installed, not all situations). The author would refuse to make a judgment in those cases, because they aren't part of the author's argument.

Robert Carroll