Lesson: Dissecting an Argument

Comment on Dissecting an Argument

Thanks for the tip on Premise-Therefore-Conclusion. This is definitely the best way to identify the conclusion if stuck between two options.

If you need practice with generating assumptions, what can I do?
gmat-admin's picture

Start studying Assumption questions and pay close attention to the nature of the correct answers.

Hello Brent, Thanks a lot for all of your CR videos. These are so helpful. I do have a question. Is there an alternate strategy to taking notes while I read? I am finding it so difficult to take notes as you've explained. It is going beyond 2 -3 mins for each question and sad part, I am not getting the answer right. Any help would be appreciated. Thanks !
gmat-admin's picture

You may just need to keep practicing.

That said, some people just don't read as fast as others, and for them, the proposed timing may be unrealistic. So, rather than read faster (and drastically reduce your comprehension), you may need to spend some time experimenting with different strategies to see which one best suits your memory and reading speed.

For example, you may need to look for questions in the Verbal section where you immediately guess and then use that extra time to ensure better RC accuracy. For example, some CR questions have incredibly long passages and very long answer choices. This might be an excellent candidate for guessing.
Keep in mind that this is a Plan B strategy.

Of course, it's best to answer every question. I'm just talking about situations in which it's really hard for students to complete the Verbal section in 75 minutes.

Hey Brent, I find it really hard to make assumptions and my GMAT is scheduled in next 12 days.
Can you advise something on how should I go about CR questions now?
gmat-admin's picture

Keep practicing - you'll get better.

That said, it's not 100% crucial that you identify assumptions when analyzing arguments (although it can help). You can often answer the question without identifying any assumptions. So, don't spend a ton of time looking for assumptions.

Hi Brent, I have a question about the last sample in the video. From the first and second premise: Giga were the only fish in the lake, and Sovkas now in the lake, do these mean now there is no Giga in the lake because Sovaks eat giga? If so, in the third premise: Sovaks eat other fish, here the "other fish" whether or include giga? This question sounds Sovkas does not eat giga to me, but then if the two fish is not contradict each other, how can we come to the conclusion that says " Releasing Dragons will let Gigas live"?

Thank you for your attention.:)
gmat-admin's picture

Hi jsuc23,

Sorry, I don't know how your question (from 3 days ago!) slipped off my radar.

Good points and good question! Perhaps I could have made the passage less ambiguous. The idea I was trying to convey is that the introduction of Sovkafish is very recent. So recent, in fact, that the Gigafish population has not (yet) been wiped out.

Also, the term "other" (as in "Sovkafish survive by eating OTHER fish") is meant to convey that Sovkafish do not eat members of their own species. Instead, they eat OTHER (non Sovka-type) fish.

So, if we accept those premises, then the release of Dragonfish should limit the Sovkafish population, which should help the Gigafish survive. Of course, all of depends on the hidden assumption that Dragonfish will focus their efforts not eat all of Gigafish

Does that help?


Hi Brent,

Thank you for your reply.

Generally speaking, the Sovkafish will eat Gigafish, correct?
gmat-admin's picture

That's correct; Sovkafish will eat Gigafish

Challenges the conclusion, means something that will go against of what's stated in the premise.
I don't understand the last example. I think all the assumptions given in the last example should be the opposite.
gmat-admin's picture

You're referring to the question that appears at 8:15 in the above video.

The question stem reads: Which of the following, if true, most effectively challenges the conclusion that RELEASING 100 DRAGONFISH INTO CHILLIWACK LAKE WILL ALLOW THE GIGAFISH IN CHILLIWACK LAKE TO SURVIVE?

The assumptions listed (at 10:10 in the video) are things that MUST BE TRUE in order for the conclusion to hold true.

One assumption is THAT the Dragonfish WON'T eat the Gigafish.
We need this to be true in order for the conclusion to hold true.
That is, if the Dragonfish DID eat the Gigafish, then the conclusion would NOT hold true.

Another assumption is that 100 Dragonfish will be sufficient to limit the Sovkafish population.
We need this to be true in order for the conclusion to hold true.
That is, if 100 Dragonfish is NOT SUFFICIENT to limit the Sovkafish population, then the conclusion would NOT hold true.

And so on.

Does that help?


okay....so the assumptions are simply the statements that must be true. we are not looking into the challenging part now, right?
gmat-admin's picture

That's correct.

Hi Brent,

at 6:04 , I wonder that "-wolves are not to be blamed for this decrease. " also be one of PREMISE as well?
If not why?

gmat-admin's picture

A premise is something that is stated in the argument. So, if "wolves are not to be blamed for this decrease" is not stated, it's not a premise.

That said, "wolves are not to be blamed for this decrease" could be considered an unstated assumption.

Does that help?


Hi Brent!
TBH, Premise Therefore Conclusion technique is amazing.

But situations where if the above technique is not possible. So, apart from that technique (Premise Therefore Conclusion) can we take this statement - “Recent Rabbit deaths are due to Max. Virus” as PREMISE? - Because it mentions a keyword of Premise i.e. “Due to” in that sentence.

In your latter videos you’ve given certain keywords for Premise as well as conclusion.
gmat-admin's picture

Keywords can certainly help identify the key components of a passage, but those keywords aren't 100% accurate. When it comes to identifying the conclusion, it helps to ask ourselves "What is the author trying to convince us of?" This will help identify the conclusion.

Hi Brent,

An assumption i.e. necessary for the conclusion to follow from the premises......Following this rule and finding my own assumptions did not lead me to choose the correct answer and don't understand where I am lagging exactly.

For me, it's taking longer to make the assumptions that match the premises AND I have tried solving a few questions in the other videos. I am not satisfied with my answers

Please let me know, Is there any other way around?

gmat-admin's picture

As I mention in my lesson on Assumption questions (https://www.gmatprepnow.com/module/gmat-critical-reasoning/video/1139), don't spend a lot of time trying to identify assumptions, because every argument we'll have tons of necessary assumptions in order for the conclusion to follow from the premises.

What's important is that you know the role that assumptions play in arguments.

In the wolves and the fish example, I seem to notice something in spotting assumptions. There seems to be direct evidence (Premises) that are given that show a relation between rabbits and wolves, rabbits and virus, but no relationship between wolves and virus.
Similarly in the fish example the relationship is stated between Dragon and Sofka, Sofka and Giga, but not Dragon and Giga( The assumption) Would this be a safe bet to take in creating an assumption?
gmat-admin's picture

Great observation! Assumptions that link unrelated entities often play key roles in ensuring/strengthening the conclusion.

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