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assumption questions

LSAT Apprentice
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Joined: Wed Dec 12, 2018 5:25 pm
Points: 12

I'm having trouble correctly identifying assumptions in the assumption questions. I can id the conclusions and sometimes the missing "part" but when I get to the answer choice I can't select the right one. I was wondering if ya'll had any tips.

Jon Denning
PowerScore Staff
PowerScore Staff
Posts: 854
Joined: Mon Apr 11, 2011 4:36 pm
Points: 1,118

Hey Faith - thanks for posting! Assumptions are, for a lot of people, the toughest question type (indeed the toughest idea) in LR on the LSAT, so I'm glad you're focusing on properly understanding them, and also glad you took the time to post :)

Let me see if I can help you out a bit!

First things first, be sure to review the Assumption content in your course books and Online Student Center, with your tutor, or in the Logical Reasoning Bible, even going over it multiple times until the notions outlined are crystal clear. They may not make every Assumption question easy/obvious—it is the LSAT after all!—but that'll be a big help. And of course if you aren't in a class ( and don't have the Logical Reasoning Bible ( I can't stress enough the value in investing in those options; they'll pay you back many, many times over when it comes time to take the LSAT and apply!

So rather than rehash the already-excellent content contained in those resources, let me supplement it with an approach to Assumption questions most people never consider: treating them like Must Be True questions!

On the surface I think most people would say Assumption and Must are dramatically different—Assumptions contain arguments while most MBT do not; Assumptions often ask you to fill in a missing piece within the argument while MBT ask you to draw a valid inference from a fact set; etc—but I've come to view them as two of the most similar question types on the whole test!

I'll explain.

The Must task is simple enough: from a limited set of information, determine what is most logically reasonable to conclude. There are subtle variations in degree with those (comprising Must Be True and Most Strongly Supported, with the latter allowing a touch of uncertainty to creep in), but overall the goal is always the same.

Assumptions on the other hand feel entirely distinct from that: determine what the author's argument requires in order to even be possible (that's the necessary part of Necessary Assumption). Or, put another way, determine what we can conclusively say the author believes in order to make such an argument. But imagine reframing that objective from a Must standpoint: if we accept the author's argument as true, believing exactly what we're told at face value, which answer choice would that argument prove to be true? So you can ultimately approach Assumptions from a Must angle, and move through the answers simply asking, "Does the argument prove/guarantee this statement?" The correct answer will be the only one that we can know with certainty based solely on what the author has told us. Just like Must Be True.

Let's play with a quick example to demonstrate what I mean.

Say I give you a belief and then we think of some Assumptions it depends on. I'll keep it simple:

..... I have a friend who is an amazing golfer.

There are two ways to think of Assumptions now: (1) the traditional way, asking what does my argument require; (2) the Must Be True way asking what does that argument prove. What we'll find is that they're the exact same things!

Requirement: My friend plays golf. If that's false (she doesn't play golf) then my argument is wrong, so it's a necessary assumption. But my argument also proves it's true: if you believe me that I have a friend who's a great golfer, then you certainly know it's true that my friend plays golf.

Requirement: My friend usually hits the ball when she swings at it. Again, if that's false and she usually whiffs when swinging, then she's not a great golfer and my argument is dead. But ditto MBT: if she's great, it guarantees she usually makes contact.

Requirement (my favorite one): I have at least one friend. Consider if that's false: if I have NO friends, then I for sure do not have one who's a great golfer and my argument is wrong. And from a Must perspective: if you believe me about my golfing friend, it proves I have at least one friend.

For comparison, let's look at something that isn't necessary:

Non-requirement: My friend won the Masters (the biggest golf tournament in the world). My argument can survive—can still possibly be true—even if my friend isn't a Masters champion, so winning the Masters isn't necessary. And what about Must Be True? Well, consider: if I told you I have a friend who's a great golfer, and you accept that as a fact, would you know for sure she won the Masters? Nope! No way. That wouldn't be proven, so it fails the Must Be True test and can't be the right Assumption answer either. (Btw that statement would be an excellent Justify answer choice, since it would prove my friend to be a great golfer)

I say all of that to illustrate that whether you can spot clearly gaps or not (and sometimes there aren't any as we explain in our Supporter/Defender Assumption model) you always have a means of attack, and then to outline precisely how that somewhat novel means of attack works (in a way that a lot of people never consider). Start filtering answers through a Must lens and watch how much easier the wrong ones are to spot and eliminate!

I hope that helps!

Jon Denning
PowerScore Test Preparation

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