to the top

#20 - Professor Gandolf says that all political systems that

LSAT Leader
Posts: 62
Joined: Sat Sep 17, 2016 9:25 pm
Points: 38

Can someone please check my diagram? I ended up with B at first, and then E the second time around:

PP (political systems that aim at preventing conflict) :arrow: L (are legit)
NPSP (those not in power are subject to the will of the more powerful) :arrow: TPC (totalitarian regimes usually good at preventing conflict)
(TS (totalitarian systems illegitimate)) :arrow: (PP :arrow: L (political systems that aim at preventing conflict are not legit/"Professor G's principle must be false")

I can see how there is no support for either B or E based on my diagram, but why is C true?
Adam Tyson
PowerScore Staff
PowerScore Staff
Posts: 2690
Joined: Thu Apr 14, 2011 5:01 pm
Points: 2,503

I think your diagram may be a bit off here, jlam. Let me see if I can help.

First sentence is Gandolf's principle, and I think you have that right (although I will use different letters to make it clearer, at least to me):

APC (Aim at Preventing Conflict) -> L (Legitimate)

Second sentence is not conditional, because it talks about what usually happens instead of what is necessary. I wouldn't diagram it myself, but if I did it would be something like:

TS (Totalitarian System) -usu-> PC (Prevent Conflict)

Notice that there is a difference between PC and APC - Preventing is not the same as Aiming to Prevent.

Third sentence:

TS -> L (If Totalitarian then not Legit)

Link that to the first sentence via the contrapositive and you get TS -> L -> APC

In other words, Totalitarian Systems must not Aim at Preventing Conflict. The author says the Professor must be wrong with that first claim, because Totalitarian Systems usually Prevent Conflict.

What's missing? What was assumed? That there is a link between Preventing and Aiming. That if you Prevent, you must be Aiming, or if you do not Aim, you do not Prevent. Something like that. In other words, the author is assuming that at least some Totalitarian Systems don't just Prevent Conflict, they Aim to Prevent Conflict. That's answer C.

Consider the negation of C - what if none of those TSs aim at PC? What if it's just incidental and not an aim? Then the Professor could still be right in his original claim in spite of the new claim about Totalitarian Systems.

I hope that helps!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
Follow me on Twitter at
LSAT Leader
Posts: 62
Joined: Sat Sep 17, 2016 9:25 pm
Points: 38

I understand C now, thank you for the explanation! I think where I went wrong was that I subconsciously equated aiming with actually preventing (which is what the author did), so I didn't even realize that I also made an assumption without realizing that I made an assumption.
LSAT Apprentice
Posts: 5
Joined: Mon Jul 23, 2018 9:28 pm
Points: 5


I selected C, but would like some more clarification regarding B. Would this answer choice weaken the argument? Because if the prevention of conflict was strictly incidental to a totalitarian system's true aims, then the author's argument would not touch on Professor Gandolf's claim regarding political systems that intend to prevent conflict.
Francis O'Rourke
PowerScore Staff
PowerScore Staff
Posts: 474
Joined: Fri Mar 10, 2017 2:44 pm
Points: 469

Hi Ja123!

You are absolutely correct here! Answer choice (B) would weaken the speaker's argument. This may be something that professor Gandolf assumes, but it is the opposite of what our speaker must assume.