The question stem says the philosopher's conclusion follows logically if which of the following is assumed.

So this is a sufficient assumption question.

The correct answer, if we add it to the argument, will make the argument valid.

In other words, it will make the conclusion guaranteed to be true.

So essentially, if you can reasonably expect an action to help the overall well-being of the people who are affected by the action, then it's morally right.

And that sounds like a principle that the philosopher might try to use to reach a conclusion.

But it looks like we're about to get another principle.

An action is morally wrong if and only if it would be reasonably expected to reduce the overall well-being of the people affected by it.

Now the phrase if and only if is creating a biconditional relationship.

In other words, what it's saying is if you reasonably expect the action to reduce the overall well-being, then it's morally wrong.

But on top of that, in order for something to be morally wrong, you have to reasonably expect it to reduce overall well-being.

That's a requirement in order to call something morally wrong.

Now in the last sentence, the author says thus, so here's a conclusion, thus, actions that would be reasonably expected to leave unchanged the overall well-being of the people affected by them are also right.

And here, when they say also right, I'm interpreting that as also morally right.

Now because we have conditional statements here, and this is a sufficient assumption problem, which typically involves trying to find links between different concepts in a conditional,

because of that, I'm going to go ahead and diagram these statements.

Now I'm not saying you have to diagram them, but I think diagramming is a helpful way to figure out what to do in this question.

Now here I've laid out the first two statements, followed by the conclusion.

Remember the first statement was a principle saying if you expect well-being to go up, then the action is morally right.

The second was, if you expect well-being to go down, then the action is morally wrong.

But here I've drawn an arrow that goes both ways, because that second sentence also means that if something is morally wrong, that means you must expect the well-being to go down from that action.

Now I'm going to return later to what this biconditional means, and another important way to understand this statement.

But here is just the initial way that you might lay out those first two statements.

Now somehow we want these statements to prove the conclusion that if well-being is unchanged, or if you expect it to be unchanged, then it's morally right.

Now let's see how we might get there.

The first thing to think about is the very first principle here, because you can see that this principle does show that something leads to morally right.

So how can I prove then that if you expect well-being to be unchanged, that leads to morally right?

Well, if I could get expecting well-being to be unchanged to lead into expecting well-being to increase, then that would get me to morally right.

But there's a problem with that potential connection.

Because if you expect well-being to be unchanged, that actually just makes it impossible for you to expect well-being to go up.

The trigger here is expecting well-being to go up.

But my conclusion is about what happens if you expect well-being to not go up.

When you say unchanged, that means not go up and not go down.

So I don't see a way to actually use this first statement here to prove my conclusion.

Unless we were to supply something that just logically doesn't make sense.

If you were able to say, when you expect well-being to be unchanged, then you expect it to go up.

I mean, in theory that could be a good answer, but logically that just doesn't make sense.

So I don't see the first sentence as being relevant here to proving the conclusion.

Logically, there's just no way to use that first sentence.

So now let's turn our attention to the second sentence.

This was the second principle we were given.

Can we somehow use this principle to show that if you expect well-being to be unchanged, then the action is morally right?

Well, let's think about that.

If you expect well-being to be unchanged, then how does that relate to expecting well-being to go down?

It means that you don't expect well-being to go down.

Because if you expect well-being to be unchanged, that means it's staying the same.

It's not going up or down.

And if you recognize that idea, then this is where the biconditional aspect of the second principle comes in.

Because remember, with a biconditional, what it means is if one side is true, the other side is true.

But it also means that if one side is not true, then the other side is not true.

So another way to phrase this second principle is if you don't expect it to go down, then that proves that something is not morally wrong.

And if you're confused by that, I recommend going back to review the lesson on biconditionals.

Whenever you have a biconditional statement, meaning a double arrow like this,

another way to phrase this idea is if A is not true, then B is not true, and the arrow goes both ways.

If B is not true, then A is not true.

For a biconditional, either both sides are true or both sides are not true.

And you don't need to flip the sides as you would with a normal contrapositive, because the arrow points both ways.

If it were a one-way arrow, then to do a contrapositive, you'd have to switch the concepts and negate.

But you don't have to do that with a biconditional.

So if you understand that second principle in this way, and then you also recognize that if well-being is unchanged,

that implies you don't expect well-being to go down, then this is something that we would already know right now.

We would be able to tell that if you expect well-being to be unchanged,

that just by its own meaning implies you don't expect well-being to go down,

and then that implies that if you expect well-being to be unchanged, you can call that action not morally wrong.

So at this point, we have enough to say, based on these premises, that if well-being is unchanged, it's not morally wrong.

What's the final missing piece here then?

How do I get from this idea to proving that if well-being is unchanged,

then something is morally right, then the action is morally right?

Well, I would just want to add on this connection,

that if something is not morally wrong, that leads to morally right.

If I could just add this blue relationship here,

if something's not morally wrong, then that proves it's morally right,

that would be able to get me from, if you expect well-being unchanged, then it's morally right.

Because if you expect well-being unchanged, then you don't expect well-being to go down,

and then that in turn means it's not morally wrong,

and then if we add that blue portion, that gets me to morally right.

So when I go to these answers, I know that I'm looking for something

that says if not morally wrong, then it is morally right,

or the contrapositive of this idea.

The correct answer could also say, if something is not morally right, then it is morally wrong.

This right here is just another way of saying this relationship.

So let's take a look at these answers now,

and we're looking for the answer that, if we add it to the argument,

is going to make this argument valid.

And remember, for the purposes of evaluating these answers,

this blue stuff right here is not actually true, it's not actually established.

That's the thing that we want to supply to this argument.

So I'm going to leave the blue stuff up,

just because we can know that this is what we're looking for,

but when you're considering the impact of an answer,

you shouldn't be considering the blue part to be already part of the premises,

because it's not.

So let's start with answer choice A, which says,

the aggregate well-being of the people affected by them.

Now this is not correct, because answer choice A is just telling me something

that I already know from the premises.

It's not giving me additional information that would guarantee

a certain kind of action is morally right.

What A is describing is the idea that an action being morally wrong

is necessary in order for us to expect that the well-being will go down.

Remember, the second sentence here, one aspect of it was,

if you expect well-being to go down, then the action is morally wrong.

A is really just another way of describing that idea.

What A is saying, in case you're curious how it looks in a diagram,

is if you reasonably expect the well-being to go down,

then it is a wrong action.

And the way that you can tell that that's what it means

is because the word only here introduces a necessary condition.

That's why wrong goes on the right side.

But as I mentioned, this idea is already something we know is true,

based on the second sentence.

It is not giving me anything new, and so it is not allowing me

to guarantee that well-being unchanged leads to morally right.

That's why A is wrong.

So in other words, if you're talking about a particular action,

there's no way that it can be both right and wrong at the same time.

But that doesn't help this argument because I'm trying to prove

that a particular kind of action is morally right.

Telling me that an action can't be both morally right and wrong

doesn't actually establish that any action is right,

nor does it establish that any action is in fact wrong.

And if that doesn't make sense to you,

then think about the statement, no cats are dogs.

Can I use this statement, no cats are dogs,

to prove that my neighbor's pet is a cat?

If I know that my neighbor has a pet,

but I currently don't know the kind of pet it is,

does this statement establish that my neighbor's pet is in fact a cat?

No, because it could be something else.

It could be a bird, right? It could be a mouse or a pet pigeon.

So in the same way that this doesn't allow me to prove that something is a cat,

and it doesn't allow me to prove that something is a dog,

B doesn't allow me to prove that something is right or that it is wrong.

That's why it's not correct.

Now just in case you're curious,

what B would look like in a diagram form

is if something is right, then it is not wrong.

Or if something is wrong, then it is not right.

But neither of those ideas help me prove that something is right.

Here you see the idea of right appears on the left side of the arrow.

That's never going to allow me to reach the destination that something is in fact right.

Next, let's consider answer choice C, which says,

And C is exactly what I'm looking for.

What C is saying is, if an action is not morally wrong,

so if an action is not morally wrong, then it is morally right.

The way that C would be diagrammed, if you prefer to think of it as a diagram,

is exactly what I have over here.

If not morally wrong, anything that's not morally wrong is morally right.

And if you're confused by that, the word any is introducing the if here.

That's the sufficient condition part, the left side of the arrow.

If you add what answer choice C says to our premises,

that gives me this portion here,

which would then allow me to prove that if you expect well-being to be unchanged,

because that implies that you don't expect well-being to go down,

which in turn implies that that action is not morally wrong,

ultimately then that would prove that that action is morally right,

which is exactly what we're trying to prove.

So that's why answer choice C is correct.

Let's understand why D and E are wrong now.

to leave unchanged the aggregate well-being of the people affected by them.

So if D is true, that's just saying that there are examples of this kind of action.

So for example, let's say someone sneezes.

That's not something you would expect to improve overall well-being

or decrease overall well-being.

It's a totally neutral effect action.

D is telling me that there are actions like that.

But the problem with D is that that doesn't prove that those actions are morally right.

Why should I call someone sneezing morally right?

That's the issue.

Remember, the blue stuff right here is not actually established right now.

Based on the premises, I have no reason to think that sneezing is morally right.

D is telling me that there are actions such as sneezing,

but that's not what I'm trying to prove.

I'm not trying to prove that these kinds of actions exist.

I'm trying to prove that if these actions exist, they're morally right.

So that's why D is not correct here.

But in order for E to be correct,

I would want to know that if you expect well-being to be unchanged,

that that is a good consequence.

I don't actually know that.

There's nothing in the premises that would establish

that if you expect well-being to be unchanged,

that that is something that is good.

So that's why E is not correct here.

Now if you're curious, the diagram form of E would be

if good consequence, then that must be a right action.

And the word right here goes on the right side of the arrow

because you have this word only.

Only introduces a necessary condition.

The right side of the arrow.

So this diagram here though, if you add it to the argument,

would not help me.

As I mentioned, because I don't know

whether anything actually has a good consequence.

Now by the way, I recognize that the way I explain this

is very heavy on diagramming.

That's because for the vast majority of people,

that's the only way to reliably get a question like this correct.

If you don't have a strong understanding of conditional logic,

then you're just going to struggle with this kind of problem.

The LSAT is essentially testing your ability

to understand conditional logic here.

Now if you think you prefer to approach this kind of problem

more intuitively, whatever that means,

I think it's certainly possible.

It's just that you'd have to be able to understand this

well enough to understand that when an action

is expected to leave well-being unchanged,

that the premises would already give us enough

to say that that kind of action is not morally wrong.

So if you can get that far,

and then you understand that we're trying to prove

that this kind of action is morally right,

that's how you might be able to sense that

this is a link that we're looking for.

I think alternatively, you could try to use

process of elimination, but even if you rely on that,

there's some part of you that would have to understand

we are trying to prove that something is morally right,

and so you'd need to be attracted to answers

that tell me what is morally right.

With that kind of understanding,

you might still be able to get to answer choice C.

But I'm not explaining this problem based on intuition,

because that's not really how the vast majority of people

are going to improve at this kind of problem.