#11 - Researchers have discovered that caffeine

[Adam Tyson]

In some contexts it could mean exactly the same amount, but in this context, where we are comparing caffeine consumption to ANY other addictive psychoactive substance, it would only make sense to interpret it as "at least as many." Otherwise, the claim would have to mean there is an equal number of people using each and every such substance. Exactly 10 million caffeine consumers, exactly 10 million cocaine users, exactly 10 million nicotine users, etc.

But even if you interpret it as meaning exactly the same number, answer E still must be true, and none of the other answer choices is supported by the stimulus, so in this case the specific interpretation changes nothing.

[wisnain]

Hi, this might be unrelated to your current question, but I have a query regarding conditional statements.
Can I take the contrapositive of statement (E) and still expect it to accurately represent the stimulus?

So, the contrapositive of statement (E) would be: If there are more people who consume alcohol than consume caffeine, then alcohol is not a physically addictive psychoactive substance.

I'm confused because I believed that "If A -> then B" represents a conditional statement, and therefore the contrapositive should convey the same meaning... but I’m uncertain if this contrapositive aligns with the stimulus.

Thank you.

[Dana D]

Hey Wisnain,

That is the correct contrapositive of Answer Choice (E), yes.

The conclusion of the stimulus states that this is significant because as many people consume caffeine as consume any one of the other addictive psychoactive substances. This means that for anything else identified as a psychoactive substance, the number of consumers must be equal to or less than the number of people who consume caffeine.

So, if alcohol is one of these psychoactive substances, there cannot be more people who consume that than caffeine. And the contrapositive: if more people are consuming alcohol than caffeine, then alcohol cannot be a psychoactive substance.

Hope that helps!

[wisnain]

That clear things up. Thanks!

Hey Wisnain,

That is the correct contrapositive of Answer Choice (E), yes.

The conclusion of the stimulus states that this is significant because as many people consume caffeine as consume any one of the other addictive psychoactive substances. This means that for anything else identified as a psychoactive substance, the number of consumers must be equal to or less than the number of people who consume caffeine.

So, if alcohol is one of these psychoactive substances, there cannot be more people who consume that than caffeine. And the contrapositive: if more people are consuming alcohol than caffeine, then alcohol cannot be a psychoactive substance.

Hope that helps!

[cd1010]

I answered C, incorrectly. I interpreted C ("Not all substances to which people can become physically addicted are psychoactive") to mean that there are some substances to which people can be physically addicted which are not psychoactive. In other words, in the broader set of all substances to which people can be physically addicted, some of them are psychoactive and some of them are not.

I thought that this is something that can be inferred from the stimulus -- that caffeine is something that people can be physically addicted to but it is not a psychoactive substance.

I'm confused why this reasoning is incorrect. Any help would be appreciated!

[Adam Tyson]

The stimulus indicates that caffeine IS psychoactive, cd. The author said that "as many people consume caffeine as consume any one of the other addictive psychoactive substances." That means caffeine is one of those substances! It would be different if that line said "as many people consume caffeine as consume any addictive psychoactive substances." In that case, the implication would be that caffeine is not one of those substances.

Since this means that caffeine is an addictive psychoactive substance, we cannot prove that there exist any addictive substances that are not psychoactive. Maybe everything addictive is also psychoactive? We can't say one way or the other based on these facts, so we have to reject answer C. The stimulus doesn't prove it.

[cd1010]

Thanks, Adam! Wow, I am now doubting my knowledge of English Is caffeine a psychoactive substance because the sentence says "any ONE OF THE OTHER addictive psychoactive substances" ? And this phrase means its IN this group?

[Adam Tyson]

That's correct! Subtle differences like this are the LSAT's bread and butter, and it's the source of some very attractive wrong answers. Every word counts!

[saiffshaikhh@gmail.com]

While I won't argue the answer choice that is correct, I don't know how we landed on using alcohol as a determinant for the answer. It seems like it is new information and arbitrary, there are other substances that can be physically addictive. Being drowsy, irritable and depressed were to me diverse symptoms, and felt that B did a solid job of answering the question.

[Adam Tyson]

Any substance could have been referenced in the correct answer, saiffshaikhh, because they said "if": if it is one of those substances, then this must be true about it. They could have said "if chocolate" or "if popcorn" or "if library paste" and it would still be correct, because of the numeric facts in the stimulus. If baby aspirin is an addictive psychoactive substance, then there cannot be more people consuming baby aspirin than the number who consume caffeine. Why? Because " as many people consume caffeine as consume any one of the other addictive psychoactive substances."

Alcohol isn't relevant here. It's just about the numbers!

As to answer B, we can't prove that diverse symptoms are typical of these substances. We only know that it's true about caffeine. Maybe that's the only substance that can lead to those symptoms? Also, we only know that happens with caffeine when the user doesn't get their usual dose. What are the symptoms when they get their regular dose? We have no idea, and thus no idea what is "typical."