#25 - Wealth is not a good thing, for good things cause no

[Administrator]

Complete Question Explanation

Parallel Reasoning. The correct answer choice is (A)

This problem combines formal logic with parallel reasoning and can be quite challenging for unprepared
test takers. Learning to identify the salient features of these problems is critical to quickly and accurately
identifying the correct answer choice.

First, recognize that this stimulus consists of a conclusion and two premises. The order of presentation
is logically irrelevant, but the method of reasoning is critical. The correct answer choice must also have
two premises and a conclusion. Also, because the stimulus is logically valid (if the stimulus contains
flawed reasoning the question stem will indicate that there is a flaw), the correct answer choice must be
logically valid. This can be demonstrated as follows:

Premise: Good things cause no harm at all

GT = good things
H = causes any harm at all

GT H

Therefore, things which cause any harm at all are not good things (the contrapositive).

H GT

Premise: Wealth is often harmful to people

W = wealth

W H

Some test takers may question this representation, arguing that it implies that wealth always causes
harm. However, the most accurate interpretation of this statement is that wealth is among those things
which cause any harm at all. This formulation is logically valid and can be appropriately manipulated to
reach the correct conclusion.

Combining this premise with the contrapositive of the first premise yields:

W H GT

That is, wealth, since it causes harm, cannot be a good thing. This conclusion is an additive inference,
correctly derived from the premises. The correct answer choice must exhibit the same pattern of
reasoning.

Answer choice (A): This is the correct answer choice. A quick glance reveals that this answer choice
also consists of a conclusion and two premises (although the order of presentation is reversed from the
stimulus). Here is the diagram:

Premise: Alex loves to golf

A = Alex
LG = loves to golf

A LG

Premise: No one in the chess club love to golf

CC = chess club

CC LG

Conversely:

LG CC

Therefore:

A LG CC

In other words, Alex, who loves to golf, must not be in the chess club. Since this conclusion is an
additive inference correctly drawn from both of the premises, answer choice (A) correctly parallels the
reasoning in the stimulus.

Answer choice (B): It should be immediately clear that the premises in this answer choice are quite
different from those in the stimulus. Closer examination also reveals that the reasoning in this answer
choice is not logically valid. The argument may be represented as follows:

Premise: Isabella smiles a great deal and hardly ever cries.

I = Isabella
SGD and HEC = smiles a great deal and hardly ever cries

I SGD and HEC

Premise: Happy people do the same.

HP = Happy people

HP SGD and HEC

Of course, smiling a great deal and hardly ever crying does not prove that Isabelle is a happy person,
anymore than having four wheels and two doors proves that a pickup truck is a Ferrari. Shared necessary
conditions do not lead to additive inferences. Therefore, this answer choice is incorrect.

Answer choice (C): This answer choice is interesting because it could use the stimulus as a principle for
justifying its conclusion. If pollution causes harm, then growth in industry would not be a good thing for
this town. Nevertheless, having a superficially similar rationale for its conclusion does not mean that this
is the correct answer choice. This conclusion is based on a cost-benefit analysis rather than an additive
inference from logical premises.

Answer choice (D): This was by far the most commonly chosen incorrect answer choice. The conclusion
is clearly an additive inference and there are two logical premises. Some test takers may even argue
that “most dachshunds hunt poorly” is very similar to “wealth is often harmful to people,” since neither
premise is universal.

However, these premises are vastly different in implication. “Most dachshunds hunt poorly” allows for
the possibility that “Some dachshunds do not hunt poorly,” which means that is it possible that for some
dachshunds to hunt very well. Therefore, the fact that Sarah’s dog hunts very well does not preclude
the possibility that Sarah’s dog is a dachshund. Here, the possibility of an exception invalidates the
conclusion.

On the other hand, in the stimulus, the certainty of an exception actually proves the conclusion. The
statement, “wealth is often harmful” guarantees that wealth will cause harm in at least one instance.
Even a single such instance proves that wealth is not a good thing since good things cannot ever cause
harm. Since this answer choice is logically invalid, it cannot be correct.

Answer choice (E): It should be quite easy to eliminate this answer choice. The second sentence is
essentially a restatement of the first sentence: If it is not a holiday, there should be more traffic. It is not a
holiday today, so there should be more traffic. Very few test takers selected this answer choice.

[catherinedf]

Hi,

I'm looking at question 25 in section 2: "Wealth is not a good thing..."

I know that this is one of those questions where I need to do a sufficient and necessary diagram, but I couldn't seem to figure out how to set it up correctly and ended up narrowing the answers down to D and A and then (of course) incorrectly choosing D. Can anyone help with how I should have attacked this problem?

Thanks for any help!

Catherine

[Steve Stein]

Thanks for your question. In this one, it might help to break down the argument from the stimulus into its logical components:

Premise: If something is a good thing, it causes no harm at all:
good thing --> NO harm ever

Contrapositive : If something causes any harm ever, it cannot be a good thing:
some harm --> NOT good thing

Premise: Money often causes harm. When we link this premise to the contrapositive above, we arrive at the conclusion as follows:

Money --> some harm --> NOT good thing

As we can see, this represents valid logic.

Answer choice A parallels the valid logic from the stimulus (although the components of the argument are not presented in the same order). This choice breaks down as follows:

Premise : In the chess club loves to golf:
chess club --> NOT love to golf

Contrapositive: Love to golf --> NOT chess club

Premise: Alex loves to golf.
When we combine this premise to the contrapositive above, we properly arrive at the conclusion as follows:

Alex --> loves to golf --> NOT chess club

Since this valid argument parallels the logic from the stimulus, it is the correct answer choice.

Answer choice D was definitely the most commonly chosen wrong answer choice, but the argument presented in this choice is not logically valid:

Premise: MOST dachshunds are not good hunters
Premise: Sarah's dog hunts very well.
Invalid conclusion: Sarah's dog must not be a dachshund

The problem is that when we are told that MOST such dogs are not good at hunting, all we know is that the majority of such dogs are not good at hunting. That still leaves the posibility that there could be some dachshunds (although a minority of them) that are good at hunting. Thus we cannot validly rule out the possibility that Sarah's dog might be a dachshund.

Let me know if this clears that one up--thanks!

~Steve

[CCLSAT1995]

Hello,
I picked answer choice D because the stimulus states that wealth is not a good thing because it OFTEN causes harm, but now always. Doesn't this logic parallel that of D, which states that MOST daschunds hunt poorly?

[Ricky_Hutchens]

Hi CCLSAT1995,

I would guess your understanding of D is why it is the most common wrong answer, but notice that the stimulus is logically sound and D is not.

Your paraphrase of the stimulus leaves out an important part. Wealth OFTEN causes harm, but good things NEVER cause harm, so wealth is not a good thing.

D says Sarah's dog hunts well, but MOST dachshunds hunt poorly, so Sarah's dog isn't a dachshund. Notice that just because most dachshunds hunt poorly doesn't mean that Sarah can't have one of the few that do. This is flawed reasoning.

Hope that helped.

[Dianapoo]

Hi!

The bible says that you don't want to confuse conditional relationships with cause and effect relationships. I was doing this question and found that conditional diagramming worked, so I'm a little confused!

Premise: G----->/H (and the contrapositive is H---->/G [keep in mind that it said "for good things cause no harm at all"
Premise: W----->H
Conclusion: W ----> /G

Put together, premise 1 and 2 come together (I think!) to make the conclusion W----->/G

So can I use conditionals when "cause" is used, and then do the contrapositive? If not, this questions is really confusing for me

[Jon Denning]

Hi Diana - thanks for the question! It's certainly an important idea, the need to separate/distinguish conditional and causal reasoning, so I'm glad you're investigating this further

The simple answer is that yes, you can for sure use conditional type diagrams when you see relationships like the ones here: "good things cause no harm at all" gives an absolute connection between good things and harm, so showing them with an arrow, as you correctly do above!, is totally fine! That is, just because the word "cause" is there doesn't necessarily make an argument causal; it's only when the author is trying to prove that one thing led to another (or one thing is the result of another) that causality is truly in play and you need to be cautious about ideas like contrapositives.

To drive this point home, consider the correct parallel/duplicate answer choice, A: there's nothing causal in it—Alex loves to golf, no one in the chess club loves to golf...those aren't active, forceful relationships—and yet it matches the structure of the stimulus perfectly. It's just partial-conditionality, where "no one in the chess club loves to golf" separates the two in a fixed fashion (conditional) and tells you something definitive about Alex.

So treating the argument here as a causal one when the author isn't really making a claim about an active/productive relationship would, in my opinion, be something of a mistake, or at least a mislabeling. This to me is more like conditionality-lite

I'll give you another quick example to show how causal language can be used in conditional/absolute relationships, and where the fixed relationship aspect is more important than the active/causal one: Imagine I told you something like "being charitable always makes people feel good." The "makes" in that is active and thus it feels causal, but the key is recognizing that it's absolute and thus can be treated conditionally, as Charitable Feel Good, and Not Feel Good Not Charitable (like "Bob doesn't feel good about his behavior last night, so it wasn't charitable behavior" or something). Anytime you have absolutes you can treat them conditionally, even if the language includes elements typically thought to be causal in nature.

I hope that helps!

[Dianapoo]

Hi Diana - thanks for the question! It's certainly an important idea, the need to separate/distinguish conditional and causal reasoning, so I'm glad you're investigating this further

The simple answer is that yes, you can for sure use conditional type diagrams when you see relationships like the ones here: "good things cause no harm at all" gives an absolute connection between good things and harm, so showing them with an arrow, as you correctly do above!, is totally fine! That is, just because the word "cause" is there doesn't necessarily make an argument causal; it's only when the author is trying to prove that one thing led to another (or one thing is the result of another) that causality is truly in play and you need to be cautious about ideas like contrapositives.

To drive this point home, consider the correct parallel/duplicate answer choice, A: there's nothing causal in it—Alex loves to golf, no one in the chess club loves to golf...those aren't active, forceful relationships—and yet it matches the structure of the stimulus perfectly. It's just partial-conditionality, where "no one in the chess club loves to golf" separates the two in a fixed fashion (conditional) and tells you something definitive about Alex.

So treating the argument here as a causal one when the author isn't really making a claim about an active/productive relationship would, in my opinion, be something of a mistake, or at least a mislabeling. This to me is more like conditionality-lite

I'll give you another quick example to show how causal language can be used in conditional/absolute relationships, and where the fixed relationship aspect is more important than the active/causal one: Imagine I told you something like "being charitable always makes people feel good." The "makes" in that is active and thus it feels causal, but the key is recognizing that it's absolute and thus can be treated conditionally, as Charitable Feel Good, and Not Feel Good Not Charitable (like "Bob doesn't feel good about his behavior last night, so it wasn't charitable behavior" or something). Anytime you have absolutes you can treat them conditionally, even if the language includes elements typically thought to be causal in nature.

I hope that helps!

Genius! Wonderful explanation holy crap! I felt smarter after absorbing your reply. Unfortunately I have a follow up prompted by your great response - When then would it be ok to convert "should" statements to conditional relationships? "One should not be dishonest if they believe X". Can we always diagram permissibility/shoulds in terms of conditional diagrams? I find that sometimes it works and sometimes it doesn't, especially when I have to do the contrapositive "if they should be honest, then they don't believe x" which just should VERY weird!!!

Thank you, you're amazing!

[Jon Denning]

My pleasure Diana!

To your question about "should," like most things to do with language it's always a bit contextual/situational.

That is, "should" can be used conditionally or not, depending on what's said and what the author intends. I'll give you a related example for each:

If we get can get tickets, we should go to the concert.

That's clearly conditional because going to the concert (or at least feeling as though they should go) is conditioned on getting tickets. So you could diagram it:

Tickets Concert

Note that it isn't quite as strong as, say, "If we can get tickets, we will go to the concert," but as long as you can spot the subtle difference between "should" and "will" (and their synonyms, like "ought to" vs "are" and "must," etc) then you'll be fine

Compare it to this:

We should go to the concert

To me, there's no conditionality present in that statement, since it's just a single point of belief. (Granted, you can make anything conditional if you're being nitpicky—If you're us, we should go: Us Concert , or whatever—but that's not helpful when it comes to the LSAT)

For your example, one way to treat the "should" part is to try to incorporate it, as in:

Believe X Be Dishonest

and

Be Dishonest Believe X (like, if soemeone is being dishonest then they shouldn't believe in X)

That may help you better distinguish between ideas of what an author feels should occur vs what will or will not occur (If you believe in X you are dishonest).

So pay close attention to how statements, whether with "should" or otherwise, are used on the test and you'll be in great shape!

Hope that helps!

[Dianapoo]

My pleasure Diana!

To your question about "should," like most things to do with language it's always a bit contextual/situational.

That is, "should" can be used conditionally or not, depending on what's said and what the author intends. I'll give you a related example for each:

If we get can get tickets, we should go to the concert.

That's clearly conditional because going to the concert (or at least feeling as though they should go) is conditioned on getting tickets. So you could diagram it:

Tickets Concert

Note that it isn't quite as strong as, say, "If we can get tickets, we will go to the concert," but as long as you can spot the subtle difference between "should" and "will" (and their synonyms, like "ought to" vs "are" and "must," etc) then you'll be fine

Compare it to this:

We should go to the concert

To me, there's no conditionality present in that statement, since it's just a single point of belief. (Granted, you can make anything conditional if you're being nitpicky—If you're us, we should go: Us Concert , or whatever—but that's not helpful when it comes to the LSAT)

For your example, one way to treat the "should" part is to try to incorporate it, as in:

Believe X Be Dishonest

and

Be Dishonest Believe X (like, if soemeone is being dishonest then they shouldn't believe in X)

That may help you better distinguish between ideas of what an author feels should occur vs what will or will not occur (If you believe in X you are dishonest).

So pay close attention to how statements, whether with "should" or otherwise, are used on the test and you'll be in great shape!

Hope that helps!

Jon thank you!

Out of curiosity would you frame PT 74 section 4 question 15 as a conditional statement? This one contains a should but I just can't categorize it based on the explanation above alone!