The premise is scientists think motivation to do important new research = worthy of colleague. Conclusion is when scientist wins renown, then scientist != colleague. So the assumption is those who win renown are not motivated, and therefore cannot be a colleague.

(D)

OG(The Bible for GMAT) Reasoning:
What assumption do research scientists make about scientists who become popularizers?

The community of scientists shares a common goal：to do important new research．What would cause this community to disapprove of a popularizer? Any scientist who becomes a popularizer appears to have given up this shared goal in order to explain science to a general audience instead．This popularizer may be assumed to have lost the motivation to do important new research．

A The issue is the scientists’ goal．not the methods they use to achieve it．

The premise is that scientists take as their colleague, only the scientists who have motivation for doing important new research.

Conclusion is popular scientists no longer can be considered as colleague.

(D) Provides the missing link... that those well known are not motivated for doing imp new reasearch. (C) maybe a reason for that, but does nothing to this missing link or Assumption. Hence D wins

C says scientists 'can' become famous without doing any important research - this doesnt mean that everyone who become a popularizer didn't do important research.
D applies to all such people. Hence D is the answer.

Lets try and do it mathematically

Generally scientists enter their field with the goal of doing important new research and accept as their
colleagues those with similar motivation. Therefore, when any scientist wins renown as an expounder of science
to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true
colleague.

1) Scientists accept = people with equal motivation
2) Scientists do not accept = people who win acclaim or Popularizers

From 1) and 2)

Popularizers do not have the motivation

Hence clearly D

Hope this Helps

Premise:
scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation.
Conclusion:
Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.

Assumption:
A populizer doesn't have motivation of doing important new research.

The explanation offered above for the low esteem in which scientific popularizers are held by research scientists assumes that

(C) a scientist can become a famous popularizer without having completed any important research
>> This doesnt answer abt the motivation in popularizer.
(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
>> Negate D and it casts doubt on conclusion.

D is correct. Here's why:

(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues --> this isn't the author's argument; he never alludes to cooperation being necessary to be deemed a "true colleague"

(B) research scientists tend not to regard as colleagues those scientists whose renown they envy --> irrelevant

(C) a scientist can become a famous popularizer without having completed any important research --> true, but this doesn't mean that that individual is not motivated

(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research --> BINGO!; if you aren't motivated to do new research, then you aren't a "true colleague"

(E) no important new research can be accessible to or accurately assessed by those who are not themselves scientists --> irrelevant

Generally scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation. Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.

The explanation offered above for the low esteem in which scientific popularizers are held by research scientists assumes that

(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues

(B) research scientists tend not to regard as colleagues those scientists whose renown they envy

(C) a scientist can become a famous popularizer without having completed any important research

(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research

(E) no important new research can be accessible to or accurately assessed by those who are not themselves scientists[/quote]

PREMISES:
1. Research scientists want to do important new research.
2. Other research scientists are considered as colleagues if they also want to do important new research (similar motivation).

CONCLUSION:
When a scientist becomes famous among the general public for explaining scientific principles, he/she (popularizer) should not be regarded as a colleague by other scientists.

PRE-THINK:
As the premise says that a scientist should do important new research to be considered as a colleague, and that popularizers are doing research to be famous, so these popularizers are not doing important new research (assumed by the scientific community).

ANALYSIS OF THE ANSWER CHOICES:

(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues.
We are concerned as to why a popularizer is not regarded as a colleague. Working by themselves or in groups does not connect the premises and the conclusion.

(B) research scientists tend not to regard as colleagues those scientists whose renown they envy.
The passage does not talk about "envy".

(C) a scientist can become a famous popularizer without having completed any important research.
"HOW" a scientist becomes a famous popularizer is not our concern; we want to know why they are not considered as a true colleague.

(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research.
This matches with our pre-thinking.

(E) no important new research can be accessible to or accurately assessed by those who are not themselves scientists.
"access and assessment of new research by non-scientists" is not talked about in the passage.

Generally scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation. Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.

The explanation offered above for the low esteem in which scientific popularizers are held by research scientists assumes that

(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues
-The argument is not about research but rather regarding scientists themselves

(B) research scientists tend not to regard as colleagues those scientists whose renown they envy
-Incorrect

(C) a scientist can become a famous popularizer without having completed any important research
-The argument is not about how the scientists can become popularizer

(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
-Correct. Since popular scientists don't have motivation that's why other scientists disregard them.

(E) no important new research can be accessible to or accurately assessed by those who are not themselves scientists
-Out of scope

Generally scientists enter their field with the goal of doing important new research and accept
as their colleagues those with similar motivation. Therefore, when any scientist wins renown
as an expounder of science to general audiences, most other scientists conclude that this
popularizer should no longer be regarded as a true colleague. The explanation offered
above for the low esteem in which scientific popularizers are held by research scientists
assumes that:

A. serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues
B. research scientists tend not to regard as colleagues those scientists whose renown they envy
C. a scientist can become a famous popularizer without having completed any important research
D. research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
E. no important new research can be accessible to or accurately assessed by those who are not themselves scientists

Can you explain how exactly is 'D' weakening the conclusion?

As written, D strengthens the conclusion (it's an assumption question, where the correct answer is a necessary premise in order for the conclusion to be true). Where you may be getting "weaken" earlier in the thread is from people critiquing/weakening the argument as given, because doing so helps you understand the gap that needs to be filled. On any Strengthen or Assumption question, attacking the argument is pretty good strategy so that you understand what makes it weak and where it most needs to be strengthened.

Notice that the premise and conclusion don't really connect here at all:

Premise: Scientists accept as colleagues those who do important research.

Conclusion: Therefore they won't welcome those who expound to large audiences.

The gap here is "what does expounding to large audiences have to do with doing important research?" --> the premise and conclusion aren't connected at all, and that's where they miss each other (one's about research, the other is about expounding to large audiences).

(D) as written helps to connect that gap: hey if you are a large-audience expounder, your colleagues think you're not interested in research. And (D) is a lot easier to find if you noted earlier what made the argument so weak in the first place.


is people critiquing/weakening the argument as given, because doing so helps you understand the gap that needs to be filled. On any Strengthen or Assumption question, attacking the argument is pretty good strategy so that you understand what makes it weak
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Eager to do research? A colleague.

Once the scientist is popular? No longer a colleague.

Why would the scientist be considered no longer a colleague? not eager to do research.

The only answer that explains the above is answer choice D

1. Read the argument
The author argues that scientists no longer regard expounders to generalists as true colleagues.

Why does he conclude this? (Evidence)
- because scientists enter the field with the goal of doing important research and accept (only accept?) those colleagues who have a similar goal

2. Know that since this is an assumption question there needs to be some evidence missing

There is a lack of clarity regarding the work done by expounders. Why can't expounders do both important research and expound?

3. Try to predict the missing piece of evidence
- Once scientists start expounding they stop doing important research
- scientists who expound do not engage in important research
- scientists who expound no longer accept their colleagues as their own

4. Eliminate 2-3 options that definitely look incorrect. Possible wrong choices are: out of scope answers, answers that repeat what is stated in the argument, or that can be inferred from the argument
A - this is not conducive to the argument
B - states that scientists dont regard other scientists who's renown they envy as their colleagues, but what about scientists who's renown they don't envy? Eliminate as this isn't relevant to the argument.
C - The method by which a scientist can become a popularizer is irrelevant to the argument
D - This fills the gap we identified above.
E - Okay, but what does the interpretation of science itself have to do with how scientists regard their colleagues? Does not add any info to bridge the gap. Eliminate

5. Negate/Deny answer choice contenders (only):
Test D (more for my practice)

research scientists believe that those who are well known as popularizers of science are notmotivated to do important new research

If scientists only accept those scientists with similar motivations to do "important research" then D clearly weakens the author's conclusion as it states that expounders actually still share this same motivation.
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Would eqivocate VeritasPrepBrian 's explanation...

Place option (D) in between the 2 sentences , you get a logical flow of the passage ....


Generally scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation. Research scientists believe that those who are well known as popularizers of science are not motivated to do important new research. Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.

Option (D) is really the assumption/missing premises !!!
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Conclusion: Renown -> Not true colleagues
Premise :
Similar Motivation -> true colleagues
Contra: Not true colleagues -> Not similar Motivation

Assumption Renown -> Not true colleagues-> Not similar Motivation
Or Renown ->Not similar Motivation