Which one of the following could be a complete and accurate list of the friends who appear together in a photograph?

T.Neill on May 28, 2020

Confused on game set-up

I watched the game-set up video, and I am confused why the instructor sets rule 1 as s-->w. Would W not be sufficient for S? I read it as if W is in the photograph then we know S is in the photograph. This then carried to rule 2, which probably led to me not doing well on this game.

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shunhe on May 28, 2020

Hi @T.Neill,

Thanks for the question! So let’s take a look at the first rule, which reads “Wendy appears in every photograph that Selma appears in.” How can we translate this into conditional language? Well, what this is really telling us is that if S is in a photo, then W is in that photo, because W is in every photo that S is in. But translating this, we get

S—>W

It doesn’t mean the other way around though. Let’s say that W is in a photo. Does that mean that S is in it? No, not necessarily. To know that, we’d have to be told that S is in every photo that W is in. But we’re not told that, we’re told that W is in every photo S is in. And so we can’t get W—>S from the first rule. Same goes for rules 2 and 3. This is definitely an important concept to master, as you’ve learned from misdiagramming this game.

Hope this helps! Feel free to ask any other questions that you might have.

Brett-Lindsay on August 23, 2020

I spent about 30 seconds trying to figure out the directionality for that one, too, until I noticed the word "EVERY," which introduces the sufficient clause. Rewritten, it states

EVERY photo Selma appears in, Wendy appears in:
S --> W

Ambria on June 5, 2021

Hi Brett! That was such a good point! Thanks!

Tebanks on March 11, 2022

I got all of this set of question wrong because I diagram it the wrong way. I thought it was W---S, S---U R----not Y. Why would LSAT trick us like that.

Emil-Kunkin on May 17, 2022

Hi Tebanks,

This question is a great example of why it is important to both read each question carefully, and to study conditional language. The lesson on sufficient and necessary is a great place, and I would also recommend taking as long as you need in your studying to get a handle on the setup, and as you practice work on time once you have accuracy down.