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Weakening the Argument


In this video, you will learn about the weaken the conclusion question type. That is, there's a conclusion drawn in the argument and you must find an answer choice that weakens that conclusion. Now, it's important to note that the word weaken will not always show up in the question itself. Sure, you may get, which of the following, if true, most seriously or severely weakens the argument?

But you may get other questions in which you have verbage such as cast the most doubt, or most seriously undermines. The point here is that you should quickly note that, oh, look, they're asking me to weaken the conclusion. Therefore, the strategies and techniques you learn in this video you'll be able to apply to the question.

Now, it's also important to note that these questions come after the paragraph, so you'll have a quick paragraph or prompt. In which you have the premises and the conclusion, then you have this question, and then of course the answer choices. Okay, now that we know how to identify a weaken the conclusion, or weaken the argument question type, let's talk about the basic approach.

You should identify the premises, or the facts in the paragraph. These usually come at the beginning in the first couple of sentences. Then you will have the conclusion. So it's usually easy to spot the conclusion, but be very careful when you're reading the conclusion, to read each word. Then think to yourself how do the premises and the conclusion connect?

Because the premises are sort of like the legs of a table holding up the table. And the conclusion is the flat part, that table itself. When you see how they're connected you should notice some gaps. In fact, the test writers write these questions so that there are these holes. And so you can think of these holes as glue, and by glue in the case of the table is not really there and so the table could fall apart.

Those are the assumptions, really, and that's why it's so important to think about the assumptions, the glue that holds the argument together. Because if you don't have these assumption or these assumptions are invalid, then the entire conclusion falls apart. What you should not do is immediately race down to the answer choices and try to find the correct answer.

You should think of these unstated assumptions. And usually you'll just wanna think of one general assumption, which is something that we'll do here in a minute with an actual practice question. And then, of course, go to the answer choices once you've thought about the paragraph at this level. First off, let's take a very sort of softball approach here by having something very simple.

This is not, of course, on the level of an actual GRE paragraph argument question. But this will help us better understand what it is to weaken the conclusion. So here we have Mike, He's the state's number one mathlete last year, that's the fact, that's a premise. He has been preparing for this year's math-lympics by studying two hours a day, that is the other fact.

Finally, there is the conclusion, therefore, Mike will win the math-lympics, that's the conclusion. That's the important part, so put a little squiggly mark where that begins. Of course, this is usually pretty straightforward when there's only a few lines. It becomes a little bit more difficult when you have seven or eight lines.

What is even trickier, of course, is identifying those unstated general assumptions. What unstated general assumption do we have here? Well, Mike won last year. And he's going to prepare for this year's Olympics, math-lympics that is, by studying for two hours.

What's the assumption? That two hours is enough preparation time to ensure that he'll be a repeat winner. So what if an answer choice is, because of increased competition, most top-ranked state mathletes have increased the number of hours they prepare. It's not exactly word for word what we have as an assumption. But it deals with the same issue, that the two hours that is mentioned in the argument itself is not enough for Mike to win again.

And therefore, the conclusion is weakened. The conclusion doesn't totally fall apart. It was only meant to cast some doubt. Let's take a look at another possible assumption. This one, of course, is a little bit more subtle. But the fact is that he was the state's number one mathlete last year, and now he's going to the math-lympics, maybe the math-lympics is a nationwide competition.

The assumption though, is that the math-lympics is not an nationwide competition. That it's simply a state competition, so Mike will win again. But if it turns out that the math-lympics includes mathletes from all 50 states, well suddenly it becomes far more competitive. And again, our faith in the conclusion is weakened.

Mike could still win, but it's not as likely. And that's kind of the correct answer. What is not a correct answer is complete destruction of the conclusion. So you will never have an answer choice such as, Mike caught pneumonia and will be bedridden during the competition. There's no way he could win, he's not even gonna show up.

Not the same as a weaken, that's basically your destroying the conclusion completely, and that will never be one of the answer choices. But it's important to know that when you're looking for an answer choice, that you're looking for one that simply casts doubt on the conclusion. So, let's take a look here at an actual question. This is a little bit tougher, but I want you to actually go through this on your own, and even pause the video to do so.

But before you do so, remember the basic approach. Read, looking for premises, spotting the conclusion. And then figure out how the premises connect to the conclusion, and what that gap is, that jump from the premises to the conclusion. And if you can identify that gap, that's the major unstated assumption. So try to do that before rushing down to the answer choices.

Once you've written down, and I'm encouraging you to write it down so you can compare what you have to what I have. Then look for the correct answer. Okay, pause the video. Okay, I assume you've paused the video. So what we're gonna do is take away all those distracting answer choices for now, and focus just on the premises, the conclusion, and the assumption.

The premises here are that there's been a boll weevil infestation for the last three years. And it's problematic, so the farmers have started to use something called Eradicon. And the reason they're using this is it emits an odor that the boll weevil hates. So those are the facts. Now we're jumping right here to the conclusion.

The agricultural board expects that cotton production on those farms using Eradicon will return to levels similar to those from three years ago. So what's the major assumption there? Well, that the boll weevil infestations are solely to blame for the decrease in cotton production. Notice cotton production's very clearly listed here, in the conclusion.

So, if there is another cause for the drop in cotton production besides the boll weevils, then all of a sudden what happens? Well, this conclusion here, that Eradicon's gonna make things better, or at least get things back to where they were before, becomes weakened. So, in terms of more specific assumptions, not that you actually have to come up with that, as long as you get the general idea of the gap in the argument.

But here's some more specific ones are that cotton crops aren't vulnerable to some other pest. There is no other factor that can affect cotton production, this is very similar to what I just said as the major assumption. Maybe a little more subtly, and this is typically what the test writers go for, not the obvious ones.

But the more subtle one would be boll weevils will not develop some immunity to Eradicon. Or even Eradicon does not adversely affect somehow the rate of production. But, of course, you don't have to actually think on this sneaky or subtle of a level. But by just thinking of the assumption, it's gonna make you a lot more prepared for what the right answer is going to be, what it looks like.

And you're going to be much more on guard against the answer choice traps that, of course, are waiting in one or two of the answer choices that are wrong. So is that the case? Were you tricked and trapped by some of these answer choices? Well lets take a look here at A, Eradicon has been proven to repel boll weevils in a laboratory setting.

Notice that this is simply consistent with what is already mentioned in one of the premises. It's not something that actually weakens the conclusion, so out with A. B, farmers in the region have a history of spraying chemicals in order to protect their crops. This shows that farmers will be likely to adopt Eradicon.

So if Eradicon is as effective as it seems to be here, then that's a good thing. Very well, the cotton production will return to similar levels. So if anything, this is kind of strengthening or lending support, we'd need weaken. And it's important to note also that, in weaken question types, oftentimes one of the answer choices will definitely be relevant to the conclusion, but it will do the opposite of weaken, it will strengthen or support.

C, most boll weevil infestations happened in the early spring, when cotton plants are highly vulnerable. We know that boll weevil infestations have happened, we know that they've negatively affected cotton production. And so C is just kind of reiterating this and giving us more specific details. But it doesn't address this assumption that there's something else going on that could possibly be affecting cotton production, or that there's maybe something off about Eradicon.

So let's get rid of C, and we're down to two answers, both of them are pretty close, they're tricky. So I'm guessing that you chose one of these answer choices. Now if you chose A through C, pause the video again and actually take a look at D and E because obviously one of them is the right answer, because they're the only ones left, and see which one you think it is.

And then give yourself a justification, why do you think it's correct? What about that answer choice is right, and just as importantly the other answer choice, what about it is wrong? And once you've done that, then we will go through and find out which one is the answer. Okay, I assume you've paused the video for that final lap.

Let's start with answer choice E. Farmers need to spray Eradicon on their fields once every few days for it to be effective. Now, if this is the case, it seems like, well, what if farmers don't spray Eradicon every few days? Isn't that sort of a high maintenance thing?

You always have to spray it on there, so maybe they're gonna forget. Well, it sounds pretty reasonable to me, so let's circle that answer. But wait a second, I'm adding information. I'm making assumptions about farmers and their work ethic, that spraying more than or at least once every few days is onerous or burdensome. And that's an assumption that I'm bringing in based on the answer choice.

And so you can make an answer choice work by bringing in extra information the way I just did. And that's what often happens in the wrong answer, they get you that way. So don't say sort of, or could have been if I assumed this. If you start using those words in your thought processes, be on guard against them.

You're likely constructing an argument to make an answer choice work, and that's dangerous. Lets look at D. When used for more than a week, Eradicon begins to leach the ground of nitrates. I know that part right there, leach the ground of nitrates, that doesn't even sound good, what exactly is leaching, and nitrates what are those?

And so It's easy to wanna just get rid of D, and then of course go to E and it's pretty easy to read and construct your argument. Then you come up with something that's not even in the answer choice itself. And the next thing you know you get it wrong. So leach the ground of nitrates, assume that nitrates are what the answer choice says, without which cotton plants cannot adequately grow.

That's what we really need to know, that by spraying Eradicon, suddenly poor cotton plants can't grow anymore because the Eradicon killed all the nutrients that they depend on. Oh, that's, that would definitely affect what? Cotton production, going back to the conclusion. Always remember the specific conclusion, and therefore D is our answer.

Okay, let's recap. What I have here is read and simply argument, and this is important. Read the argument and simplify it as well, think of it in your own terms. You can say okay, there's this boll weevil infestation, and It's happened for the last three years, farmers are gonna start using this chemical. The reason I do that is it simplifies the barrage of information and it makes it easier to think about the conclusion and of course the unstated assumptions.

And that's of course the next step, think of the major assumption, just that one major assumption. Don't sit there all day coming up with four or five, that's not the point. The point is for you to get started thinking of some holes in the argument so you can better identify the correct answer. And of course, you want to make sure that you kind of anticipate the answer after you've come up with the major assumption.

And then go through every answer choice, not spending too much time on any one answer. Now, I don't think number four applied too much to this question, cuz it's not as hard as some of the other paragraph arguments. But sometimes you'll see an answer choice that seems to work. For instance, answer choice E, let's say it had been answer choice A or B.

Don't think oh that works pretty well, let's just circle that and move on. Make sure to go through each one, and then in the end you'll realize that there's usually two of them that both kinda seem to work. And that's when you want to apply kinda that analytical muscle that we used earlier. One way, of course, is to make sure that the answer choice directly attacks the assumption, it addresses information in the conclusion, and that you're not adding this extra information.

Well, if farmers are lazy and then they don't spray Eradicon every day it's not gonna work. That of course was mentioned, that's us making this inferential jump and bringing our own assumptions into the question. Something we should always avoid doing.

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