#22- A tax preparation company automatically adds the

[Adam Tyson]

To your first question, answer D is not a conditional statement. The best way to negate a "some" statement is to say it's the opposite of some, which is none. Some of your friends are athletic? No, none of them are. Some of these towels are dirty? No, none of them are. Etc.

And to your second question, this answer has nothing to do with negating a statement in the stimulus. It has to do with dealing with the other possibility. We already know that if the email does suggest something illegal, the disclaimer won't protect them. But there's another possibility: what if it does not suggest something illegal? Couldn't it offer them some protection in that case? How can they possibly claim that the disclaimer serves no purpose? Answer A deals with that alternative possibility by saying in that case, you don't need protection. That proves that it serves no purpose.

"If you go to the party, you'll have a lousy time. Therefore, you are going to have a lousy night."

"But what if I don't go to the party? Couldn't I have a good night then?"

"No, if you don't go to the party, you will also have a lousy night."

[Dancingbambarina]

crispy,

The conclusion is the last sentence, and that's not a conditional. In Adam's post viewtopic.php?p=62346#p62346 you can see Disclaimer has Purpose as the conclusion, and that's not a conditional...it's the necessary condition of the conditional. So it can't be a contrapositive.

So we have in the stimulus: Something Illegal Legal Protection Disclaimer has Purpose. The conclusion is the final necessary condition. All of those premises are conditional, and we can't infer any particular condition of any of that. We want to reach the necessary. We could get there if we knew the email elsewhere suggests the client do something illegal. That's fine, but no answer choice does that. Instead, an answer provides another conditional - the email could not elsewhere suggest the client do something illegal, and still the disclaimer offers no protection (because none is needed).

It's similar to the following: "If Philadelphia scores at least 14 points, I'll win my bet. Therefore, I'll win my bet." I could prove the conclusion two ways: if Philadelphia scores at least 14 points, I'd certainly win. But if I could provide another premise like "If Philadelphia scores fewer than 14 points, I'll also win my bet," I would definitely win my bet, because Philadelphia will either score 14+ points or not, and either way, I win. So I win no matter what. That's what happens with answer choice (A).

Robert Carroll

Hi Robert,

This makes total sense. I am just confirming this line of reasoning is strictly for Justify questions, and not for strengthen questions. Very rarely is the polar opposite the correct answer, unlike here, where to get to the necessary, we need the polar opposite.

Surely the argument on its own would suffice? Why do we NEED to add something else?

Thank you.

[Jeff Wren]

Hi Dancingbambarina,

No, the argument on its own doesn't suffice. As a general rule, no Justify question will contain an argument that is already valid. There will always be a missing piece in the argument, and the correct answer will provide that missing piece. Of course, there can be more than one way to justify an argument.

Let's look at an example of a simple conditional argument using letters as our terms.

Premise: If A, then B.
Conclusion: Therefore, B occurs.

Now this argument is not valid, because we do not know for certain that "B" occurs.

What would justify this argument?

If we knew that "A" occurs, then we'd definitely know that "B" occurs, so that would be one way to justify the argument.

However, there is another way to justify this argument, which is if the logical opposite of A also guarantees that B occurs, this would also justify the argument.

If we knew that "Not A -> B," then no matter whether "A" occurs or does not occur (the only two possibilities since they are logical opposites), "B" will occur.

While this concept isn't tested too often on the LSAT, it is something that you should understand in questions involving conditional reasoning, usually in Justify and Must Be True question.

One last observation, the two conditional statements are not opposites. They have opposite sufficient terms, but lead to the same necessary condition, which is perfectly fine. They do not contradict each other in any way.