We call this question a sufficient assumption question.

The question stem reads,

which one of the following is an assumption that would allow the conclusion to be properly drawn?

The key word here is...

words, I suppose, is assumption and properly drawn.

Why is it called a sufficient assumption?

Because with this assumption, that's enough,

that's sufficient for us to say that we have a properly drawn conclusion,

which means we have a valid argument.

So the idea is that right now, without this assumption,

because we haven't said this assumption yet,

without this assumption, this argument is not valid,

which means that the conclusion could still be false even if all the premises are true.

So we need to find this...

So, you know, so we have to figure out what the premises are,

what the conclusion is,

and then we have to say which one of these answer choices,

if we add it into our argument along with the other premises,

will force the conclusion to be true.

That's how you get to a properly drawn argument.

That's how you get to a valid argument.

So let's read the stimulus first.

And by the way, all that stuff is just covered in way more detail

over many, many lessons that probably span hours,

but, you know, obviously we can't go into that right now.

But all those lessons are in our full course.

But I'm pretty sure we can still understand this even with...

I'll just mention the lessons that are sort of relevant.

Great. So what's this government policy?

Right, how does this...

I mean, I presume it's a public health policy

that is going to help us avoid the serious cases of the flu.

This goal will be accomplished by the annual vaccination.

So here we go. Here's how we're going to do it.

We have annual vaccinations of high-risk individuals.

Who are high-risk individuals?

Well, they are the elderly, as well as people with chronic diseases,

which probably, you know, have lower... they have poor immune systems.

So those are the groups.

So every single year, our 65 and older group

and our health-wise, immune system-wise weak group,

they're going to be vaccinated.

And each year's vaccination will protect only against the strain of influenza virus

deemed most likely to be prevalent that year.

Okay, so whatever year it is, year one,

in year one, the vaccination will protect...

So how many... you know, you got to think about how many different strains of flu virus are there?

Maybe millions, who knows, right?

But so what we're going to do is we're going to pick,

of the millions of flu viruses, we're going to be like this one, this one right here.

You know, like this is all the strains of like flu viruses.

In year one, what we're going to do in year one,

we're going to say, hey, this guy, this guy is the guy we think that is most likely to be prevalent this year.

So this is the guy that we need to watch out for.

So we're going to immunize you two against this guy.

But from this, that's all the premises tell us, right?

That's all the premises tell us up to here, premises.

But the conclusion is that so every year will be necessary for all high-risk individuals,

that's these two guys, for every year,

we have to give them a vaccine for a different strain of the virus.

Wait, why is that? Why can't we give them the same vaccine every year?

You see, how do we determine what vaccine these two groups get?

Well, remember the process? The process was we asked our...

I don't know who it is, the person in charge of the CDC.

And we asked this person, what do you suppose,

what do you deem to be the most likely prevalent strain of influenza for year one?

And he says this thing. So then we take this, make it into a vaccine, give it to them.

Why can't it be this thing again? We asked him next year, in year two,

why can't he be like, you know, in year two, right?

You see, we're saying that year two, it will be this thing that he picks

and he'll give a vaccine based off of this thing, this different strain to them.

That's the conclusion. And then in each year, it will be a different one,

which that's, you see, that's making an assumption.

The presumption is that he's not going to say,

oh, you know what, last year, it was the avian flu.

This year, it's going to be the avian flu again.

So give the same thing to them again. This is definitely not okay,

because if this were okay, this whole argument falls apart.

Right? So in every year, it's not true that in every year,

it would be necessary for high-risk individuals to receive a vaccine for a different strain.

You see, so what we, what they're presuming is that the person who's deciding

what's the most likely prevalent strain of virus will decide each year that it's a different virus.

He has to. And if he does, then our argument's great.

But if he doesn't, our argument falls apart. So that's pretty much it.

So that, you know, that's like saying there's 10 million people in this group,

and there's 10 million people in this group, and year to year, it won't change very much.

But that doesn't, who cares? That doesn't, you see, that's totally,

completely irrelevant to the issue at hand, even though it sounds and reads very relevant.

You know, it's making you think, oh, well, like, how many people really are going to be vaccinated or whatever.

But it just doesn't, it doesn't do anything to make these premises force this conclusion to be true.

Well, I mean, sure, I'm sure it does, right? This year, a serious influenza, the chance of it is 5%.

Next year, it would be 10%. The year after that would be 8%.

But again, so what? I can't do anything with this information.

That's not going to force this to be true. How is it going to be the same?

Is it going to be different? We're none the wiser.

That's just, I mean, that's also not going to help us.

So each vaccination, but there's a tricky answer choice, which, you know,

this answer choice says each vaccination only protects against one strain.

But you see, it still doesn't, I mean, that's great that it strengthens the argument,

but it doesn't get us to validity. It doesn't allow us to make this argument perfect.

It could still be, even so, that the, even though that the vaccine protects only against one strain of virus,

it could still be that year to year, the person who's deeming what the most prevalent strain is

picks the same one every single year. He picks the same one.

Year two picks the same, year three picks the same, year four picks the same.

And do you see how, like, the fact that vaccines only protect against one strain,

that doesn't prevent this from happening, which that's, this is a death knell of our argument.

Our argument can't have this thing happening. Our argument has to say that it picks, you know,

Each year, the strain of influenza virus deemed most likely to be prevalent

will be one that had not previously been deemed most likely prevalent.

So if year one, we're going with this, year two, you can pick anything you want,

but you cannot pick this, which is great because that's exactly what we need.

We need to pick a different one. Pick a different one, then boom, you know, you got a different vaccine.

Year three, you pick a different one. Whatever you pick,

it just can't be something that had been picked before the previous years.

So see, this ensures, this statement, along with our premises, forces our conclusion to be true.

That's how we get a right answer choice for a sufficient assumption question.

This is sufficient assumption question is actually quite unrepresentative of sufficient assumption questions.

A lot of sufficient assumption questions on LSAT are, use heavy formal logic.

So, you know, like, all A's are B's. We have an A, therefore we have a B.

So something like that. But that's, you know, this question doesn't allow us,

doesn't grant us a detour into that, but, you know, some other sufficient assumption.

I'm sure we'll come across another sufficient assumption question,

and I'm sure we'll get a chance to do that.

Fewer side effects? Seriously? Like, it just doesn't, I mean, nobody cares about side effects.

And then they try to explain why each year will have such side effects. We care even less.