Must Be True | LSAT Logical Reasoning

This lesson covers Must be True questions in the Logical Reasoning section. It's a question type that's a good foundation for the entire Logical Reasoning section. It explains how to draw an inference from a set of facts, the reasoning structures that apply to Must be True questions and the Trap Answer Patterns to look out for.

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[harshithamarathe]

I love how you break down the arguments and show the relationships between statements so well. I’m preparing for GMAT but this was probably the clearest way someone has explained arguments. Thank you so much!

[taylor]

Thank you for taking the time to make and upload this video and all the other videos in this series! I have found them very helpful! You are a blessing!

[isaiahkim]

I've always wanted to know the types of reasoning methods and their frequencies in a question type. Your contents are very useful to prepare how to approach each reasoning structure. Thank you!

[Lgionr]

Thanks dude! Hope that your recovered from that cold.

[dianachang]

Very good explanation! I have been struggling with this type of LR question.

[Shawn]

Thanks for the videos, these videos are saving my rear end.

[Reese]

Thank you so much! 7Sage goes to mechanically on these types of questions.

[MorganHorse]

Listening to the first example has me feeling like such an idiot lol. If this premise is applied to something, I’m very good at these questions through context. But with this, I’m struggling to follow. That said, I’m multitasking. Maybe I’ll come back to say I figured it out.
How I know that P is not L just because P is not M without the nuance of what they actually are?
Edit: yep I got the first applied question right lol. I just don’t like making assumptions.

[matenina]

When taking the timed lsat do you recommend diagramming each question with the causal/conditional relationships?

If not how do you keep track in your head especially on virtual tests?

[taylorneu]

How does the relationships imply the reverse at 11:23 prove the inverse is wrong? I don't follow the logic of "if you reverse it its not true". Wouldn't you be able to invert both sales decrease into sales increase creating rising profits, and only selling coffee into increased products with the statements you've listed?

[oliverupload]

Interesting but I don't believe this is correct (18:55). Why is B) "too strong" when the statement is literally word for word in the paragraph: "Danaxil - stops pain more quickly." If we are taking the advertisement at face value this is exactly what it's saying. In mathematical terms that would indicate Danaxil headache time < competitor head ache time which is answer B). The answer choice of C) in mathematical terms would indicate Danaxil head ache time <= competitor ache time, which is not stated in the advertisement. If we are not taking this at face value then there is no judgement we can be making at all, because the advertisement can be completely false.

[ravisandhu]

At 23:40 you state that you cannot negate in the forward direction. However, in the causation video, Patrick stated that no cause, no effect or less cause, less effect is a correct answer choice in causation-based reasoning questions. Is there a difference between these two ideas?

[blingbling]

that second question is trifling as fuck

[ВиталийОвчаренко-тй]

In the context of LSAT Logical Reasoning, the phrase "Must Be True" refers to statements that are necessarily accurate and supported by the given information or arguments within a particular question or passage. These statements can be deduced logically from the premises provided, and they represent the core conclusions that one can draw based on the available evidence.

In order to identify "Must Be True" statements in LSAT Logical Reasoning questions, you should carefully analyze the provided information and arguments, and look for the most reasonable and well-supported conclusions that can be derived from them. This often involves understanding the relationships between different pieces of information, recognizing logical fallacies or inconsistencies, and considering the context in which the statements are made.

To excel in LSAT Logical Reasoning, it is essential to practice identifying "Must Be True" statements and strengthen your critical thinking and logical reasoning skills. This will help you not only in answering LSAT questions accurately but also in developing a strong foundation for legal reasoning and analysis in your future law studies and career.

[francescacolby]

What if conditional statements don’t link. What do u do then?

[francescacolby]

How is D for the last question negation. To me it seems to be reversal and negation.

[Bossanik]

What's the difference between Casual and Conditionals, these two are often easy to confuse, can you do some videos in this subject?

[GopiRamanathanLSAT]

@LSATLab How are "must be true" and "could be true" questions different from one another? Do the tactics change in any significant manner between those two varieties of question, or would the approaches mostly be the same? I'm assuming you may have a video on this but I'm not sure which one it is haha

[anirbanmukherjee]

(1) K or L —> M. (2) NOT K —> L. Taking the contra positive of 1, NOT M —> NOT K AND NOT L. But NOT K —> L (as given in 2). Contradiction in the setup?

[Mayelinida]

But doesn’t the wording matter? I thought about that when looking at option A but then I thought it says K or L and not K and L… Please can you explain