How to know when conditional or subset

nelson1234

Hello everyone,

I am currently doing some LR problems and I've had a recurring problem. When writing out conditional statements, I am sometimes confused whether a subject is part of the conditional statement or it is a subset of another item. This is best illustrated in an example. On preptest 21, LR 2, section 3 question 22 the stim states: "Anatomical bilateral symmetry is a common trait..." When doing the problem I wrote: ABS --> C. However, in his explanation JY simply put C, rather than the conditional relationship. So how do I know when to write a conditional or when to indicate a trait/subset by itself (ABS is common = C - ABS vs ABS--->C)?

Thank you in advance for your help.

FaviPapi-1-1

Hey!

I am unsure on what you mean by this: "[w]hen writing out conditional statements, I am sometimes confused whether a subject is part of the conditional statement or it is a subset of another item."

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Remember that diagraming is a method to help you understand what is written in the stimulus. That said, were I to diagram the phrase, I would have done it like this: ABS ---> CT....

I hope this helps!

Chris Nguyen

Hey @nelson1234,

Let me try to answer your question in parts:

"I am sometimes confused whether a subject is part of the conditional statement or it is a subset of another item."

If you think about it, conditional statements are basically just subsets! For example, take the phrase "If you're a dog, then you're cute." Dog is just a subset of things that are cute. In addition to that, it's also a conditional statement! You can think of them as the same thing.

Here's a question that you didn't ask, but I think will be helpful (backseat lsat help, sorry )

"Why use one way to diagram and not the other?"

It depends on whether or not it's helpful to use a conditional statement or not in context with the stimulus. In the question that you referenced, JY deemed it not so helpful for us to diagram the first sentence as a conditional statement. It's much easier to just call that thing C when you read the whole thing and realize that all we are doing is negating the necessary condition to get to the valid conclusion.

But if you did diagram it as a conditional statement, you'd still come up with a valid digram map. It just might be a little more convoluted than what JY did. The goal of diagramming is to make our lives easier. It's just a means to an end and we use it to translate complicated language. So we can represent things in however way that it will make us solve the problem easier.

If we did it your way and used a conditional statement, we'd get:

ABS ------> C (ABS is a common trait)
/CA ------> /C (If ABS did not confer advantages, it wouldn't be a common trait)
C ---------> CA (This is the contrapositive of the above)
ABS -------------> C -------------> CA (This is the statement chained up)

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ABS -------> CA (If you're an ABS, then you're a common trait, ORR you can just say 'ABS is a common trait')

Which is basically the same thing as what JY said, represented differently. The only reason why you'd do it one way or the other is to make it easier on yourself to realize the argument structure. I hope you see it's really just a different way of representing it, and conditional statements are essentially subsets.

I hope this was helpful to you! Let me know if you have any questions!

nelson1234

Hey @christopherr

Thank you for the explanation! Was extremely helpful.

In order to ensure that I fully understand, I just wanted to confirm my thought process. Basically, rather than mapping out the conditional statement, JY simply pushed ABS into the domain of discourse. Similarly, the statement 'anyone can go to the park if you are happy' can be translated as Happy --> Park. The domain of discourse in this example is any human, given the 'anyone' in the phrase. Without the domain of discourse the conditional statement would be: Happy ---> Human --> Park.

Thanks again. Please let me know if I am correctly understanding.

Chris Nguyen

@nelson1234

sorry for the late reply but yes! That's exactly it

Happy LSAT studying!