Q8 - Grasses and woody plants are

[aebq196234]

on this question I got that the answer is E but A was tempting. is A wrong because the things don't co-occur but one precedes the other?

[ohthatpatrick]

(A) describes the recurring flaw of Correlation --> Causality.

Get real familiar with what this flaw is, because many trap answers will incorrectly say this flaw is occurring, simply because the test writers know that this language is frequently appealing to people.

Correlation --> Causality sounds like this:
A recent study found that people who own high definition TV's are more likely than those who do not to attend professional sporting events. Thus, it seems like seeing a crystal clear image of a sporting event on TV creates an appetite to see such an event in person.

A real simple way to reduce to symbolism is:
Ppl who are A tend to be B.
Hence, being A causes you to be B.

If you're ever tempted to pick a Correlation --> Causality answer choice, you can quickly verify that you have these two statements that each involve the same 2 things. The first statement links them together statistically. The second (the conclusion), links them together causally.

In terms of Q8, there's no way this could be a Correlation --> Causality argument, since the conclusion says the rodent-eating predators will cause erosion to be prevented.

In order for (A) to be right, we would need something like this premise:
"In areas in which there are rodent-eating predators, the rate of erosion is much lower than in areas in which rodents are free to burrow into the dirt."

If we went from ^that^ idea to the actual conclusion, then (A) would be the correct answer.

Let me know if you were thinking about two other events as the "two events" this question was referring to ... but also know that on Flaw questions, our correct answer choice is supposed to describe why it was incorrect to reach the Conclusion drawn, and so (A) would need to be addressing predators/erosion as the two events.

p.s.
(B) describes the recurring flaw of "generalizing from an atypical sample".
(C) describes the recurring flaw of "circular reasoning".

Recurring flaws are frequently wrong answers. The more certainty you have about what these flaws look like when they're really happening, the easier it'll be for you to quickly/confidently eliminate answers describing recurring flaws when they aren't applicable to the given argument.

Hope this helps.

[WaltGrace1983]

When I was doing this section timed, I initially chose (A) and confidently eliminated (B) (C) and (D) but was unsure about (E). I had 45 seconds left at the end of the section and so I went back and looked at this question again. From re-reading the premises I underlined, I quickly saw my error and chose (E). Here was my reasoning:

Roots keep embankments from eroding

Grass clippings cause roots to rot
+
Grass clippings attract rodents that damage roots

-->

Bringing in predators to eradicate rodents will prevent erosion

Here was my fatal error: I didn't fully understand that the rodents CAUSE the damage to the roots too. I glazed over those very important words and basically took the stimulus as saying that grass clippings cause roots to rot and grass clippings cause rodents. Period. Why was this fatal? Because it turned my thinking around. Because of this flawed understanding, I was thinking along the lines of, "well if we get rid of the rodents, we would just be getting rid of one effect of grass clippings! if we get rid of this one inconsequential effect of grass clippings who cares? This got me really turned around and it made (A) really attractive because I didn't realize that the rodents actually did CAUSE (though they are not the only cause of) erosion. I hope this all made sense. However, it just proves that these LSAT designers have a keen sense of how to make wrong answers appear really really attractive.

The correct reasoning:
Okay so we have two things happening and they both indirectly cause erosion. (Clippings --> Rotting roots) & (Clippings --> Rodents --> Rotting roots). Rotting roots --> Erosion. Okay, this all makes sense. However, how can we say that just fixing ONE cause of erosion will fix erosion? We can think of this in a few ways. I will try two of them.

#1. An argument could say "being hungry causes one to eat a Snicker's bar...therefore if one is not hungry one will not eat a Snicker's bar." We can all see that this is an illegal reversal and this is basically what is going on here. We have "rodents --> rot --> erosion." Yet does this mean that "~rodents --> ~rot --> ~erosion?" ABSOLUTELY NOT! There can be a million and one causes of erosion or rotting and just because we get rid of one cause doesn't mean anything. ~rodents does NOT entail ~rot or ~erosion (look up mistaken reversal in conditional logic if you don't understand this).

#2. We could make this argument even simpler. We are given two potential causes of rotting, and thus erosion. Let's say that these are the only two causes of rotting and erosion in the whole world! If we get rid of one -just one- does it necessarily following that there is no rotting or erosion? Nope! Here is the flaw and this is what (E) outlines.

(A) is wrong in one sense because these events (grass clippings and rodents burrowing) do NOT merely "co-occur." Grass clippings CAUSES the rodents burrowing and damaging the roots. I think that this is what (A) is getting to at least. This might actually induce a question on my part. When we are given statements like (A) when it vaguely talks about "two events," how do we interpret that? In this stimulus there are many events that are occurring (grass is causing grass clippings, those are causing rotting roots and rodents, rodents are causing rotting roots, rotting roots are causing erosion, etc.).