Psychologist: Identical twins are virtually the same genetically. More

Question

Psychologist: Identical twins are virtually the same genetically. Moreover, according to some studies, identical twins separated at birth and brought up in vastly different environments show a strong tendency to report similar ethical beliefs, dress in the same way, and have similar careers. Thus, many of our inclinations must be genetic in origin, and not subject to environmental influences.

Which one of the following, if true, would most weaken the psychologist’s argument?

(A) Many people, including identical twins, undergo radical changes in their lifestyles at some point in their lives.

(B) While some studies of identical twins separated at birth reveal a high percentage of similar personality traits, they also show a few differences.

(C) Scientists are far from being able to link any specific genes to specific inclinations.

(D) Identical twins who grow up together tend to develop different beliefs, tastes, and careers in order to differentiate themselves from each other.

(E) Twins who are not identical tend to develop different beliefs, tastes, and careers.

Bunuel · Accepted Answer

EXPLANATION FROM Fox LSAT

Think about the Winklevoss twins. Even if separated at birth, and brought up in dramatically different environments, wouldn’t they both, just based on their size and frat boy looks, be required to row crew in college and have careers in investment banking? Sure, their physical characteristics are genetic in nature. But that’s not the same thing as a genetic inclination to want to become an investment banking douchebag. Perhaps  other people  just look at them and say, “Here’s your key to the executive washroom, sir,” regardless of what they actually want to do with their lives.

Similarly, you could take two hideous little Danny DeVito babies and put them on opposite sides of the world, in drastically different circumstances, and even if they both want to become President of the United States, the world is going to take one look at them and usher them directly to the nearest garbage dump. Hey, I’m not saying this is fair. All I’m saying is that it  could  happen, which means the logic of the psychologist’s argument is suspect.

We’re asked to weaken the psychologist’s argument: “The world treats physically identical people the same way, even if they are brought up in dramatically different areas and circumstances,” would be a great weakener. The psychologist basically says the Winklevoss twins will end up as investment bankers because they are genetically inclined to do so, and I would counter with, “It’s not because of  inclination , it’s because the world sees their blonde hair and blue eyes and immediately thinks they are The Man. So it’s actually an environmental influence after all.”

A) I don’t see how this has anything to do with anything.

B) So what?

C) Nah. Just because scientists can’t currently link specific genes to specific inclinations does  not  prove that inclinations aren’t caused by genes.

D) My first response to this answer is that the argument is only about twins who grow up  apart . So I thought it was irrelevant. But I’ll return to it in a second.

E) Fraternal twins aren’t at issue here. The only twins that were mentioned in the study were identical twins. This only strengthens the argument, because it shows that twins who are genetically identical end up the same, while twins who are not genetically identical end up different. This would suggest that genetic inclination is really important, as the psychologist suggests. We needed a weakener, so this is definitely out.

Okay, so I eliminated all five answers. I’m okay with this. If this doesn’t happen from time to time, you aren’t being critical enough. I’m going to return to D, because I think I can make a case for it: If D is true, it’s an example of genetically identical twins being influenced by their environment. If the Winklevi grow up apart, they both end up as investment bankers with wives named Buffy. But if they grow up together, one of them looks at the other and says, “Oh my God, I don’t want to become a douche like you,” and grows his hair out and moves to Belize. That’s a clear example of how environment (the presence of the other twin) has affected the Winklevi!

Our answer is D, but I couldn’t see it until I’d eliminated all five answers. Tough question.

Nidzo · Answer

(A) Irrelevant. This does not tackle the argument of 'genetic vs environmental' influence.  Incorrect

(B) This choice still maintains that genetics plays the greatest role, thus it does not weaken the argument.  Incorrect

(C) Irrelevant to the argument.  Incorrect

(D) This shows that genetics may not be the main reason for our inclinations.  Correct

(E) This choice strengthens the argument.  Incorrect

Answer D

bhavyagmat · Answer

Psychologist: Identical twins are virtually the same genetically. Moreover, according to some studies, identical twins separated at birth and brought up in vastly different environments show a strong tendency to report similar ethical beliefs, dress in the same way, and have similar careers. Thus, many of our inclinations must be genetic in origin, and not subject to environmental influences.

Which one of the following, if true, would most weaken the psychologist’s argument?

(A) Many people, including identical twins, undergo radical changes in their lifestyles at some point in their lives.

lifestyle is too vague..still reasonable - this is a case for identical twins and we cant weaken with a trait shared by many people

(B) While some studies of identical twins separated at birth reveal a high percentage of similar personality traits, they also show a few differences.

This may weaken a bit but we dont know about where the differences came from

(C) Scientists are far from being able to link any specific genes to specific inclinations.
not linking with specific inclinations will not affect the fact that overall linkage exist

(D) Identical twins who grow up together tend to develop different beliefs, tastes, and careers in order to differentiate themselves from each other.

this shows that genetics didnt work and other factors did

(E) Twins who are not identical tend to develop different beliefs, tastes, and careers.

not relevant as about twins

tomloveless · Answer

I don't know...... "D" seems as though twins are doing a deliberate action in order to differentiate themselves versus being raised separately and becoming similar through a genetic disposition. In fact, if twins were raised together, that would introduce too many variables to even be a viable comparison to those raised apart, as pointed out in "D", the deliberate action of varying behavior. They don't seem related to me and seems out of scope.

bhavyagmat · Answer

That was my initial reading too and that is quite right to an an extent. But here is the nuance - even if it was deliberate - identical twins were able to overcome the genetic aspect, to whatever extent..but surely 100% dominance of genes is weakened when they overcome exactness of inclinations expected as a result of them being identical twins.

In fact then I went to and fro with Chatgpt about it. The thing subconsciously that occurred (at least for me) when I discarded D ( and marked B) was that I softened the conclusion

I am attaching raw ( though a little verbose) extract of conversation I had with Chatgpt, which I have stored in my error log. Hope it helps and helps you gain a perspective which unambiguously brings out D as solution

My input 
"Intially i felt D was irrelevant as i felt identical twins tending to develop differences to differentiate themselves from each other   doesnt hurt the fact that the genetics is dominant....  
And B had a tinge of weakening though not quite as required. So went with B"

What Chatgpt told me
(a) You mentally softened the conclusion.
The psychologist’s literal claim was “our inclinations are genetic and not subject to environmental influences.”
But when you paraphrased it, your mind likely turned that into something like “genes play a dominant or major role.”
That softening—from an absolute (“not subject”) to a comparative (“mostly genetic”)—is subtle but crucial.
Once you reframed it that way, you naturally thought:
“Even if environment sometimes makes twins different, genetics can still be dominant — so (D) doesn’t really hurt the argument.”

You discounted (D) because it seemed off-topic and assumed genes could still dominate, thereby mis-scoping the conclusion and picking (B) for its contextual similarity.

Psychologist: Identical twins are virtually the same genetically. More

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Psychologist: Identical twins are virtually the same genetically. More

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