Q24 - Ecologists predict that the incidence

[ManhattanPrepLSAT1]

The best way to handle this Match the Reasoning question is to sort out the logic quickly, know what you need to parallel, and look for small deviations as you move through the answer choices to eliminate as many answer choices as possible.

The reasoning from an abstract perspective is

X or Y → Z
~Y → X
--------------
Z

(A) the conclusion is negated from what it should be. The conditional relationship in the first sentence predicts that crime will increase. In order for this to be the correct answer the conclusion should state that crime will increase. However, the conclusion states that crime will not increase.
(B) fails in the second sentence. It should be a conditional relationship that relates educational funds and recruiting qualified teachers.
(C) is the correct answer.

IR⇑ or ~CD⇓ → IN⇑
CD⇓ → IR⇑
---------------------
IN⇑

(D) has the conclusion wrong. We’re looking for the assertion of the necessary condition, rather than it’s denial. So, the conclusion should have read, "Thus, the incidences of skin cancer will increase."
(E) inserts the word "and" in the first sentence. It should have said "or."

[lisahollchang]

One thing I've found helpful with this type of question is to diagram the stimulus, then AS I read each question draw lines or variables to follow each argument where it goes. The correct answer will lead me in the same direction that the stimulus did. At the end, my paper looks kind of messy with some lines and arrows next to each answer.

[eunjung.shin]

One question on C.

The stimulus says " the use of pesticide is known to contribute to global warming"

But the C says "if there is a decline in the demand for consumer goods, that will lead to higher int rates." -> that is conditional where the sufficient needs to be triggered to come to the conclusion whereas the stimulus is a statement.

Does that still make the reasoning parallel?

[jimmy902o]

^^ I second this.. isnt there a difference between "use of pesticides is known" to the conditional "if" in C?

[carlin.odonnell]

One question on C.

The stimulus says " the use of pesticide is known to contribute to global warming"

But the C says "if there is a decline in the demand for consumer goods, that will lead to higher int rates." -> that is conditional where the sufficient needs to be triggered to come to the conclusion whereas the stimulus is a statement.

Does that still make the reasoning parallel?

The statement in the stimulus is conditional as well:

"the use of pesticides is known to contribute to global warming"

This is the same as saying: If pesticides used --> lead to increase in global warming.

[asafezrati]

One question on C.

The stimulus says " the use of pesticide is known to contribute to global warming"

But the C says "if there is a decline in the demand for consumer goods, that will lead to higher int rates." -> that is conditional where the sufficient needs to be triggered to come to the conclusion whereas the stimulus is a statement.

Does that still make the reasoning parallel?

The statement in the stimulus is conditional as well:

"the use of pesticides is known to contribute to global warming"

This is the same as saying: If pesticides used --> lead to increase in global warming.

I disagree.

"known to contribute" doesn't make the use of pesticides a sufficient condition for a continued global warming effect.
Pesticides might be responsible for 1% of the rate of global warming. If we cut other factors which contribute much strongly for global warming (factory farming and trasnportation, for example) and encourage other factors that can reverse it, there is a fair chance we will be able to increase the use of pesticides and halt global warming at the same time.

I don't see this gap in answer choice C, but it is still the best answer.

[JeremyK460]

I thought this argument was awesome! The question stem is whatever, but this is actually a very controversial syllogism. Whether it’s valid or not is still up for debate!

Breakdown:
Premise: If global warming continues or pesticides aren’t expanded → malaria cases increase
Premise: Use more pesticides → global warming increases
Conclusion: Malaria cases will definitely increase

‘Known To’ & ‘Sufficiency’:
This tripped me up for a second. How do I perceive this argument? Is this in essence conditionality...causality? The way I approached it (under time) was like: Who cares? They’re the fucking same right now! But, going back to the issue I had, how I look at the relationship between pesticide use and global warming depends on what the effect is. I came up with this analogy. Let me know if it’s good!
Vitamin B12 is known to contribute to reforming bone marrow.
As there are many contributing factors to global warming, there are also so many contributing factors to reforming bone marrow. Pesticide-use and vitamin b12 both supplement the effect they contribute to by way of escalating their respective process. Also, I started thinking down the line of ‘perhaps pesticides (or not all) do not contribute to global warming’. But, honestly, what world would I be living in if pesticides didn’t contribute to global warming? Not this one. The evidence tells me that the pesticide’s contribution is known. Well, if pesticide’s contribution is known (definition: something that is accepted, familiar, or famous) then it’s justified by a direct appeal to the people's general experiences / knowledge. So, with this being thought, I was able to look back at the statement and think: the use of pesticides is sufficient to contribute to the global warming problem. I get it, maybe the average amount of pesticide use contributes an almost unnoticeable amount. But is that really enough to say that it isn’t sufficient to contribute at all?

Conditionality / Causality:
Doing this question timed, I tried to determine whether there was conditionality, causality, or whatever being used, but I totally gave up on that after about a minute. I was like: ahhh conditional indicator...causative indicator...they’re everywhere! I said fuck it. I’m going with conditionality. IDK! Going back and giving it a good stare (and some ‘search), I think looking at this from a propositional / syllogistic standpoint is most appropriate. According to An Introduction to Traditional Logic by Scott M. Sullivan, he explains this to be a ‘basic’ formula for Pascal’s Wager: a very controversial syllogism used by Socrates. So cool! Basically, you’re pinned against the horns without a third alternative, because of the conjunctive premise (the second premise) and how it establishes the constructive dilemma (but for so many controversial reasons). In formula, it kind of looks like this...

P1: not-A or B, then C.
P2: A or B
C: Therefore, C.

Long winded breakdown, I’m sorry! The major premise is a conditional statement; it presents two different antecedents and two identical consequents. The minor (constructive) premise affirms the alternative antecedents of the major premise. The conclusion affirms its consequence. So, it’s like…

If I exercise at the gym, I will get in shape.
If I exercise in my bedroom, I will get in shape.
If I’m not exercising at the gym, I am exercising in my bedroom.
Therefore, I will get in shape!

It’s pretty cool. This argument is valid depending on who you’re reading! If anyone wants to talk about this, I am so down!

Answer Choices:
(A) This is just the opposite idea. It looks like: If not-X is done or not-Y is done, then Z will happen. If we do Y we will be able to do X, so not-Z will happen. The counter-premise establishes the idea that both disjuncts can be denied together, and that this would draw a prediction contradictory to the presented prediction.

(B) The second premise accepts one of the sufficient conditions of the disjunct and draws its logical conclusion. This is different from the second premise in the stimulus’s argument. By way of implicature, the second premise in the stimulus’s argument becomes exclusive.

(C) This nails it! The second premise establishes that the relationship between the two presented disjuncts have an exclusive relationship of sorts. The explanation above should be enough!

(D) The reasoning is different. This is pointing out that there was an overlooked ignored common cause. The conclusion contradicts its claimed prediction and justifies it by considering an ignored common cause (between the two presented disjuncts).

(E) This is the contradiction of the previous answer choice. The second premise points out an ignored common cause between the two presented conjuncts (supposed to be disjuncts) and its effect.