42 comments

  • 5 days ago

    This helped me really process what I was doing wrong. Correct me if I'm wrong but when doing Sufficient assumption questions, the new concept is in the conclusion and not in the premises. Meanwhile Necessary assumption questions have "new concepts" but here it's known as the "missing piece" and it's found in the premises not in the conclusion

    2
  • Wednesday, Apr 8

    Amazing lesson. I have struggled a lot with NA questions on recent prep tests, but I felt the Core Curriculum was not really what I needed to re-review. This high level summary was perfect. After reviewing this video and taking notes on the main lessons, I think I was able to identify the key areas I was struggling with. Thank you very much!

    2
  • Edited Monday, Apr 6

    I ended up picking D because I knew A was reversed. But the word "sometimes" in D threw me off. If making major changes in their behavior is the necessary condition, doesn't the word sometimes make the answer wrong?

    0
    Kevin_Lin Instructor
    Monday, Apr 6

    @praksesprepper The premise tells us that reptiles are "incapable" of making major changes in behavior. So the link the author assumes is:

    incapable of major changes --> incapable of complex reasoning

    contrapositive:

    capable of complex reasoning --> capable of major changes

    D says sometimes because it's matching up to "capable of major changes". In fact D would be wrong if it said "if reptiles were capable, they would always make major changes" because that's too extreme for the actual line of reasoning.

    2
    Monday, Apr 6

    @Kevin_Lin That makes sense- thank you so much!!

    0
  • Tuesday, Mar 3

    im scared

    2
  • Tuesday, Mar 3

    Ahhh yes my biggest weakness

    4
  • Tuesday, Feb 24

    Is it possible to get transcripts for the video lessons?

    3
    Kevin_Lin Instructor
    Friday, Feb 27

    @tspinnanger I'll look into it. Instead of a transcript, I might just include a summary of the takeaways below the video.

    7
    Kevin_Lin Instructor
    Tuesday, Mar 24

    @Kevin_Lin I'll be adding a short text summary of key points to each lesson. Should occur within the next week or two.

    3
  • Edited Monday, Feb 16

    i always confuse sufficient and necessary. i can always narrow it down to 2 possible answers, yet i tend to choose the one that confuses necessary and sufficient. i dont know how to correct this ugh.

    1
    Kevin_Lin Instructor
    Saturday, Feb 21

    @Ssss Return to the Conditional and Set Logic module -- this is probably the source of a lot of your confusion with sufficient and necessary conditions. It can take a lot of practice to get fluent in these concepts.

    2
    Tuesday, Feb 24

    @Ssss One thing that helped me when I was first starting with conditional logic is to map out every single question and answer that uses conditionals.

    I would take a practice question under normal time control (ie try to answer efficiently), then on blind review, I would diagram the question, understand from that diagram what piece was missing that I should be looking for, then diagram all the answers, and understand why the wrong answers didn't fit/interact with the diagram of the question.

    This will help you actively expose yourself to sufficiency/necessity, and you will soon be able to "diagram" mentally and see the missing pieces without having to put pen to paper.

    2
  • Sunday, Feb 8

    for some reason I do better on necessary assumption question than sufficient assumption questions... I'm just so confused on why necessary assumption makes more sense to me than sufficient. I think I view them as the same? is there a specific difference between them that others have noticed?

    3
  • Saturday, Feb 7

    I feel that this is my weak suit lol

    4
  • Edited Friday, Jan 16

    Such a helpful explainer with great take-away tips; thank you Kevin!

    One question: in Question 4 re: macaque monkeys, you mentioned that B is easy to negate because you can just take away the "not" in a sentence that is "Subject is not Predicate", ie negated AC becomes "Subject is Predicate".

    Is it it always okay to do that, or are there some parameters around when we can do that? (for example, if the Subject is singular not plural)?

    Or are there cases where just dropping the "not" may not work how we need it to for a negation test? Ie, where taking a way the "not" needs to be a "some" instead of "all" relationship? ie, "Subject is not Predicate" needs to be negated to "Subject is SOMETIMES Predicate" or "Some Subject(s) are Predicate" to properly evaluate whether it breaks the argument?

    2
  • Thursday, Jan 8

    Is it wrong to assume in Q2 AC A is too broad as well because it says "Animals" As opposed to the reptile in question? It feels like a subtlety that the argument is not as broad as AC A makes it out to be?

    1
    Kevin_Lin Instructor
    Wednesday, Jan 14

    @Danny_F I think this is debatable. The "reptile" aspect of the argument didn't seem to be play a role in the logic, so arguably the author's assumption isn't narrowed to reptiles alone.

    1
  • Edited Saturday, Jan 3

    WOW 7 hit me luck a truck, Thank you Kevin, you have been so helpful.

    4
  • Monday, Dec 29, 2025

    HOLYYYY question 6 was not it man.

    7
  • Sunday, Dec 28, 2025

    this is super helpful.

    which lesson would you advise is best for becoming a pro at negation?

    1
    Kevin_Lin Instructor
    Sunday, Jan 11

    @e.wimoine The second half of the Logic of Intersecting Sets module discusses this! But you bring up a good point; maybe there should be a Fast Track - Negation

    7
    Friday, Jan 16

    @Kevin_Lin yes, a Fast Track - Negation video would be super helpful! Especially where negation leads to double negatives; how we can read them in a way that makes more sense.

    3
    Friday, Feb 13

    @Kevin_Lin Yes please!

    2
  • Thursday, Dec 11, 2025

    These lessons are incredibly useful, but there has been an issue with it buffering indefinitely very frequently. Is this happening to anyone else, or is this a me problem?

    8
    Monday, Dec 29, 2025

    @Tateclarke24 Yes, I'm having the same issue with the buffering starting in the middle of the explanation for question 6. Frustrating....

    1
    Kevin_Lin Instructor
    Monday, Dec 29, 2025

    @whouse737 Have you encountered this for other videos?

    1
    Edited Monday, Dec 29, 2025

    @Kevin_Lin Yes, for me, it also happened in the Must Be True video, shortly after you started diagramming, (I think that was question 5?). I still got a lot out of it, but it would have been great to finish it.

    2
  • Wednesday, Dec 10, 2025

    These lessons are incredible.

    However, I see so many gaps in my ability with NA because of it. haha. This is probably the most difficult concept for me and has been throughout my entire study journey.

    Thank you for bringing more clarity to this challenge.

    3
  • Tuesday, Dec 9, 2025

    I really appreciate these additional lessons.

    3
  • Friday, Dec 5, 2025

    The key takeaways at the end are so helpful. I can understand the questions on their own, but finding patterns in logic is harder to grasp when working on my own. I believe pattern recognition separates the good from the great. this is FANTASTIC.

    3
  • Thursday, Nov 27, 2025

    #5 C looks pretty good, even after hearing why it's wrong :'(

    3
    Monday, Dec 1, 2025

    @owenm I thought of it as what if someone works really well for 40 hours but anymore leads to worse performance. As in there's no difference between like 10 and 30 hrs. Does that mindset help?

    3
    Sunday, Feb 8

    @WilliamZiebellRichards I feel like C to me doesn't even look that great but it seems no worse than A which is a difficult thing to contend with

    1
  • Saturday, Nov 22, 2025

    These are wonderful and really helping me to identify the areas that I need the most practice in. I must say though.....the 'Moses of the hot spring' line really made me laugh.

    2
  • Friday, Nov 21, 2025

    THANK YOU! This is super helpful!!

    3
  • Monday, Nov 17, 2025

    This is absolutely superb!

    3
  • Sunday, Nov 16, 2025

    Super helpful!! Please keep making these fast track videos. I feel like they solidify the core curriculum, and are perfect to watch when I need to review the approach to a specific question type at a high level, and not re-watch question specific lessons.

    4
  • Sunday, Nov 16, 2025

    yayyyy new video!!! thank so much Kevin! Just finished this and looking forward to future fast track videos!!!

    2
  • Thursday, Nov 13, 2025

    These are the perfect videos for me. I always struggle to stay alert when the explanations are too long or in depth because I understand the basics. These fast-track videos have helped me understand these questions types a lot better. Please keep making these.

    7

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