Also, not sure if I am mistaken, but for question 1 I think that he wrongfully said in the video that when we negate X → H (X ←s→ /H) we are supposed to consider that some could be anything between 0 and except 100. Shouldn't this be anything between 1 and except 100? Given that some means "at least 1"

In order to determine when to interpret "all" as a quantifier or as a conditional indicator to figure out my approach to negating the claim, I always ask myself if the claim is talking about a "universal statement about a group" or if it is more of a "rule that shows a necessary condition." If it's the first case, I interpret all as a quantifier and the negation as A ←s→ /B, if it's the second case and all is a conditional, then I use the A and /B negation - is this correct?

Does anyone know a way to visually represent this with circles that would represent sets? Similar to what he did in the previous lesson about negating all?

Does anyone know what symbol we should use to represent overwhelming majority in lawgic form?

This might be a silly question, but "several" was listed as a quantifier that indicates an intersectional relationship a few lessons ago but I don't see a lesson dedicated to it... Does anyone know if we should think of it as the same as "many"? And in that case, would it be considered equivalent to "some" as well?

Quick tip: it always helps me so much to draw the subsets and supersets for each the questions! That way I can visualize what is being said and fully comprehend what the sentence means and why one things guarantees another, etc.

So, in this case we can say that this argument is valid (conclusion follows logically from premises based on what we learned about contrapositive arguments) but it is on the weaker side because it relies on an assumption (unstated premise) to provide support to conclusion. In the beginning I was confused and thought that valid arguments had NO ROOM for assumptions but now I see that assumptions have nothing to do with validity/invalidity (which are determined by the structure of the argument) but rather with an argument's strength level.

To me, this standard lawgic "formula" for valid conditional arguments is super helpful because it lets you easily spot an invalid argument, it's simply the argument that does not follow the standard

A --> B

X^A

-----

X^B

An example that I came up with that helped me picture all of this is "All cats are mammals. Jojo is a cat, therefore, Jojo is a mammal." This clearly follows the standard equation above. But if the argument is "All cats are mammals. Jojo is a mammal, therefore, Jojo is a cat" then the argument is invalid as it would be translated to

A --> B

X^B

----

X^A

There is a gap in the reasoning here and the conclusion (Jojo is a cat) does not follow from the premises (Jojo could be a dolphin, a dog, pig) therefore, it is invalid.

I believe that the Disney argument is the strongest because the conclusion ("therefore, Walt must have offered...") is very clearly supported by all the information in the premises previously provided - it leaves us no doubt that, since he is able to download his Genie+ pass via the app and has never prostrated himself to anything, the only option left is offering propitiations to Mickey Mouse since those are the only two viable routes to get the Genie+ pass. The tiger argument comes second because, although the premise offers certain support to the conclusion, it feels like we are taking information from a very specific and narrow group of mammals (tigers) and using it to make a general conclusion about a much broader group. The trash bin argument is the weakest because it leaves us a lot of room for questions - although the author's rationale makes sense here, it might seem like a stretch to conclude based on the premises provided that the cat is certainly guilty.

I got this right but was confused about whether for a lot of the options we could say "consistent" for Jo when all we know is that she believes that productive → alone and, therefore, /alone → /productive and so we don't know she feels about /productive people... For A I was very tempted to say "unsupported" for Jo because she doesn't address /productive in her statement but after doing some research I realized that on the LSAT we must understand that if something does not contradict a rule (for example two productive people working together) then that is CONSISTENT with the rule. However, if it is the case that we don't have enough information to determine if something contradicts or is aligned with a rule THEN that is UNSUPPORTED - we just don't know. Here, in A and in other cases, we knew that /productive people working together was not breaking Jo's rule so that is considered consistent

Speaking from a more "lawgic-oriented" perspective, I said that C is wrong because it confuses necessity for sufficiency (oldest mistake in the book as he always says) - based on the stimulus we can only that if there is no bacteria eating plankton that guarantees that there is no agricultural runoff (contrapositive of what is said in stimulus: /agricultural runoff → /bacteria) but not having agricultural runoff does not ensure that there will not be any bacteria to devour plankton

One thing that I noticed - and please correct me if I am wrong - but I believe that besides the fact that B is an example of "the oldest mistake in the book," meaning that it reverses the conditional relationship making it look like if 250+ population → SS, it also wrongfully uses "exceeds 250" since the stimulus clearly states that SS → at least 250 (meaning, a population of 250 or more). So even if this option was re-written to indicate the right conditional relationship, if it did not replace "exceeds 250" with "at least 250" or "250 or more" it would still be wrong because it would say "if the population of panthers is ever SS it exceeded 250" which can be translated to SS → 250+ - which is different from what the stimulus says (SS → at least 250)

Did anyone else eliminate E because of the different "degrees of certainty" in the stimulus vs the answer choice? The stimulus clearly states that NO antibiotic that has been tested against bacteria X has been able to eliminate it and the rule in stimulus states that bacterias develop resistance to ANY antibiotic used against it (unless they are able to eliminate it completely). To me that sounds much stronger than saying that X is more resistant to "at least some" antibiotics that have been used against it - in my opinion that implies that maybe X became resistant to only some of the antibiotics that did not eliminate it, which goes against the rule

I got this right but for the wrong reason I guess - what really confused me here was the fact that the stimulus used awards as a way to indicate that small companies had superior designs - I interpreted this as not being an indicator of one's quality (someone might have connections that ensure that they will get award, etc.). I think that this is a good reminder for me not to let my own biases and outside knowledge interfere with my rationale and stick to the stimulus