Logical Reasoning

The takeaways

- Sufficient Assumption-type questions contain arguments that are dependent on conditional language, think “If…then.”

- There will be a disconnect — a missing link — between the premises (statements presented to us as evidence, and we will accept as true) to the conclusion (the claim that the argument LSAT author is trying to convince us of and is not necessarily true).

- Your job is to assume the answer(s) to each answer choice's question, and then ask yourself; will this information, depending on which way it goes, either strengthen OR weaken the author's conclusion in the stimulus?

- SA questions are a type of formal logic question, which means it is also possible to diagram out the answer through conditional language and symbolic logic.

This blog is a part of the “Approach Question Type” series and like all articles in this series will focus on step 4 of the “Analyze Stimulus” step. If you need a refresher on how to approach LR questions generally, make sure to check up on our blog "How to Approach the Logical Reasoning Section.”

**Table of Contents:**

- What is an SA Question?
- How to Approach SA Questions
- Example

What is a sufficient assumption question? The goal of a sufficient assumption question is to fill in the logical gap between the premises and the main conclusion by injecting a *sufficient assumption *operator, which, *if true*, no doubt logically guarantees the conclusion.

If we look at the root of the logic behind an SA question, then we will see that an SA question functionally acts as a *strengthening *operation to the argument. In fact, it is the *strongest, most certain *strengthening operation, because, if the additional evidence provided in the answer choice is true, it will be *sufficient *to conclude what the author is trying to conclude in the stimulus.

Let’s quickly make sure we understand some foundational information here so we know what to look for in terms of the components of an SA-type question.

Question Stem Examples

- “The argument’s conclusion follows logically if which one of the following is assumed
- The conclusion can be properly drawn if which of the following is assumed?
- Which of the following if assumed, enables the conclusion?

Once you’ve read the question stem, identified the SA-type question, and actively read the stimulus to determine what the argument is, we will then need to analyze the stimulus to figure out the answer. This article as mentioned will discuss “step 4” of our LR Approach guide which is to “analyze” the stimulus.

Here is a step-by-step guide for us to find logical gap(s) in SA Questions!

- 1) figure out what is in “common” between the premise(s) and conclusion
- 2) figure out what is “different” between the premise(s) and conclusion
- 3) pay particular attention to logical conditional indicator language (can we make any “if” statements?)
- 4) remind ourselves: what is the “goal”, or the conclusion we need to end up at?
- 5) look to connect what is in common with what is different between P→C to get us there.

Premise: California is a state within the United States of America.

Conclusion: Marie is in the United States of America.

Let’s go through our step-by-step checklist. The first two steps is to ask ourselves, in trying to find the disconnect and thus fill in the gap of the missing link, is *what is different and the same *in both the P and C?

- Common: Both the P and C mention “USA”
- Different: P mentions “California,” while the conclusion introduces “Marie” who is suddenly in the USA.

Now, let’s figure out if there are any logical indicators or if→then statements we can make in the stimulus.

- If statements premise: If in California → in USA

Remind ourselves of what the goal is: sufficiently guarantee the conclusion.

- Our goal: What information (assumption) will prove Marie is in the USA to be true, based only on the singular premise we have in this argument? We need to somehow make a logical flow and get Marie to end up at → USA

So the gap is Marie → ? → USA

Find the missing link and fill in the logical gap

- So the missing link, the “gap” we need to insert into this argument to
*prove*the conclusion will involve both what can be found in the P and C, by linking that with what is*different*.

Can you predict what information or evidence can we inject into this argument to *prove *that Marie is in the United States? Remember that the goal of an SA question is to fill in the gap from P→C.

**Sufficient Assumption Answer:** Let’s assume Marie is in California, therefore we know she must be in the USA.

Here is it mapped out in **formal logic**: Marie → California → USA

Let’s try another example!

**Premise: **To be a legally practicing lawyer in the United States you need to have passed the bar.

**Conclusion: **Mike Ross has passed the bar.

Again, let’s go through our steps:

- Common: “passing the bar”
- Different: The premise mentions “practicing lawyer” whereas the conclusion introduces “Mike Ross”
- If statement premise: If legally practicing lawyer → passed bar
- Goal: we need to somehow make a logical flow from Mike Ross → passed the bar.
- What information or evidence can I inject into this to
*prove*that I have passed the bar? We need to fill in that gap by providing additional evidence that suggests the premises are*sufficient*enough to*guarantee*the conclusion.

**Sufficient Assumption Answer:** Mike Ross is a legally practicing lawyer (even if that’s not true in the show “Suits”!)

**Formal Logic**: Mike Ross → legally practicing lawyer → passed the bar

—

So what’s next? Remember our 5-step checklist for analyzing sufficient assumption answers, and start putting it into practice in real LR questions. You can drill only SA-type questions right on AdeptLR!