Can someone tell me the Assumption here

Question

Dear experts  AjiteshArun ,  KarishmaB ,  MartyMurray ,

Can you please help me identify the Assumption in the following argument:

Jordan has scored A-grade in Physics. So, Jordan is smart .

Thanks in advance.

AjiteshArun · Answer

Hi mpobisetty,

One assumption that will help us get from the support to the conclusion is "Anyone who scores an A-grade in Physics is smart".

mpobisetty · Answer

I thought this too as well. But, my colleague says that the assumption is:

Some people who score an A-grade in Physics are smart.

His point is that if we negate the assumption, the conclusion must become invalid.

If we take the following as the assumption:

Some people who score an A-grade in Physics are smart.

The negation will be:

No one who scores an A-grade in Physics is smart.

This negation clearly invalidates the conclusion that Jordan is smart.

On the other hand, if we take the following as the assumption:

Anyone who scores an A-grade in Physics is smart.

The negation will be:

Not everyone who scores an A-grade in Physics is smart.

This negation does not necessarily invalidate the conclusion since Jordan may be in those people who scored an A-grade in Physics and are smart.

Would appreciate your comments.

KarishmaB · Answer

You need to specify what kind of assumption you are looking for.

Some people who score an A-grade in Physics are smart.

This is a necessary assumption - the assumption we talk about in GMAT usually. Upon negation it breaks the conclusion.

Anyone who scores an A-grade in Physics is smart.

This is a sufficient assumption. One that leads us to the conclusion. GMAT could give you this too. 
Its negation may not break the conclusion.

mpobisetty · Answer

Thanks for the insight. Now that I think about it, my impression was that assumptions are always supposed to be necessary.

Do assumptions questions explicitly mention in GMAT whether we should be looking for necessary or sufficient assumptions?

I just looked up few Assumptions questions and the question typically is:

Which of the following is an assumption on which the argument depends?

Would this qualify as a necessary or sufficient assumption?

KarishmaB · Answer

Default is necessary. 
Sufficient would be "conclusion logically follow if which of the following is true..." - sufficient assumption

mpobisetty · Answer

ok, so revisiting my original argument:

Jordan has scored A-grade in Physics. So, Jordan is smart.

The "default" assumption would be:

Some people who A-grade in Physics are smart.

This is quite an eye opener for me.

While doing Google search, I came across the following page that seems to explicitly address this difference between necessary and sufficient assumptions:

https://www.800score.com/gmat-prep/prep-guide/sufficient-necessary/

egmat · Answer

mpobisetty - Please do not overcomplicate things by looking at necessary vs sufficient assumptions. It will not help you in CR (may be in formal logic, but not in Critical Reasoning).

Please watch this video. Hopefully, it helps - https://www.loom.com/share/c28f92308f1b ... 38d820fa93

-Rajat

AjiteshArun · Answer

Hi mpobisetty,

You're on the right track. If you see the word  depends , you're almost certainly looking for a necessary assumption.

If you'd like to know more about how the two types are different, you could go through this session:

https://www.youtube.com/watch?v=TiluhG2JJiU

mpobisetty · Answer

Thanks a lot for this very insightful video Ajitesh ji. Truly appreciate.

mpobisetty · Answer

Thanks for recording the video Rajat ji. It helps.

Antonynguyen · Answer

In the argument "Jordan has scored A-grade in Physics. So, Jordan is smart," the assumption is that scoring an A-grade in Physics is a reliable indicator of intelligence or being "smart."

This means the argument presumes that good performance in this specific subject correlates with overall intelligence, which may not necessarily be true. The reasoning is flawed if there are other factors at play, such as the possibility of Jordan having access to extra resources, being particularly skilled in Physics alone, or other contexts that may not reflect overall intelligence.

Can someone tell me the Assumption here

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GMAT Critical Reasoning (CR) Questions

Can someone tell me the Assumption here

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