Free LSAT Course > Logical Reasoning > LSAT Reasoning Intro

 (00:1) Intro |(3:48) Demo Question | (11:41) Trap Answers | (13:41) Difficulty | (19:03) Summary
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The three parts of most Logical Reasoning arguments: Premise(s) + Assumption(s) = Conclusion

Premises

These are statements that support a conclusion. They are like evidence.

Indicator words:

  • Since…
  • Because…
  • Due to…
  • Studies have shown…
  • As indicated…
  • Given that…
  • This can be seen from…

Assumptions

While the conclusion and the premises are stated in the argument, assumptions are not. On the LSAT, it’s a crucial skill to be able to identify any assumptions, or gaps, between the evidence and the conclusion.

Indicator words:

Assumptions have no indicator words because they are unstated.

Conclusions

You may be asked to identify the conclusion, strengthen it, weaken it, identify why the reasoning in the argument is flawed, or find an answer choice with parallel reasoning to the argument to reach the conclusion.

Indicator words:

  • Therefore,…
  • Thus,…
  • Hence,…
  • So,…
  • Accordingly,…
  • For this reason,…

No one ever said the LSAT was an easy test; don’t expect the test writers to make it as simple as described above. Expect patterns such as Premise + Premise = Sub-Conclusion + Premise = Conclusion. We’ll be reviewing these complex structures later in the course.

Next LSAT: January 13th

Parts of a Logical Reasoning Question

The Passage

The first segment of the question contains an argument or just a series of facts. The premises in the Passage on the LSAT are true. Don’t argue with them. So, in this example, you should assume that the price did increase sevenfold for the purposes of the question.

The postal service of Fairfield is badly mismanaged. Thirty years ago, a first-class letter delivery cost only three cents. The price has increased sevenfold since then while the reliability and speed of the delivery have declined.

The Stem

The Stem (aka “the stimulus”) is sometimes in the form of a question and sometimes written as a statement. Be on the lookout for words like “EXCEPT.” The importance of the Stem is that it will give you a clue about the question category (giving you a huge insight into the question). We’ll spend most of the Logical Reasoning course reviewing these 20+ question categories.

Each of the following weakens the above conclusion EXCEPT:

The Answer Choices

There are always five possible choices. Your job is to figure out the one answer that satisfies the requirement in the “best” way. Often this is most efficiently done by finding something “wrong” with 4 out of the 5 answer choices. Other times, one answer will jump out as definitely “right.”

A. The volume of mail handled by the postal service has increased dramatically over the last thirty years.

B. Unprecedented increases in the cost of fuel for trucks and planes have put severe upward pressures on postal delivery costs.

C. Private delivery services usually charge more than the postal service does for comparable delivery services.

D. The average delivery time for a first-class letter three decades ago was slightly longer than it is today.

E. The average level of consumer prices overall has increased fourfold over the last thirty years.

Four-Step Method to Solving Logical Reasoning Questions

Step 1:
Understand the Stem

The LSAT commonly uses only about 20 or so question stem types. In this course, we go through these question stem types so you can get a jump start on the question just by reading the stem.

Step 2:
Read the Question

Read carefully and efficiently! You can’t skim much. You’ll need to look carefully for important keywords to identify conclusions and premises.

Step 3:
Predict the Answer

Before you read the answer choices, it can be helpful to come up with your own answer to the question. Don’t try to predict the exact answer, but just get a general idea so you don’t blunder blindly into the answer choices.

Quit?

If the question is far over your head, it’s time to consider flagging the question and skipping it for now.

Step 4:
Evaluate the Choices

One or two of the answer choices will be absolute junk, so you can make it easier on yourself by eliminating a few from the start. Work as systematically as you can. Time is a factor, so don’t get into the habit of spending minutes debating your choices.

Double Check?

If you are prone to careless errors and have extra time, take a moment to double check your answer. You can also note the question to return to it later.

Question Types

Our Logical Reasoning course is organized by the major Logical Reasoning question types. We’ve broken them down into five chapters:

LSAT Prep Mindset Video Summary

  • 00:01 – The LSAT requires a critical and skeptical mindset. You must evaluate arguments actively.
  • 00:14 – It also requires curiosity about unfamiliar topics.

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Logical Reasoning Seminars

The Logical Reasoning chapter begins with a short course in Formal Logic.

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Next LSAT: January 13th