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Logical Comparison 3,739 views

Teacher/Instructor Eva Holtz
Eva Holtz

Harvard University
Perfect scores on the SAT and 4 SATIIs

Eva is a certified admissions counselor and the founder of PrepPoint, a premier test prep company in the San Francisco Bay Area.

In this episode, we're going to talk about logical comparison which happens all throughout the SAT writing section on all question types and there are four rules that go into logical comparison.
First, you need to compare equivalent concepts. Second, use the comparative and superlative forms properly. Third, don't compare something to a group it's part of without also including the words "other" or "else" and lastly, be clear what you're comparing with what else you're comparing. Let's look at those four rules in more detail.
So the first rule in logical comparison and the most important rule for the SAT, is that comparisons must be apples-to-apples, meaning that you have to compare things that are of the same type and we'll look at some examples in a minute so you'll know what I'm talking about. Now, if the comparisons aren't already apples-to apples, you have to look for an answer choice that fixes the problem in three ways: you can either repeat the apples which we'll see in the example. You can use 's, the word 'that' or the word 'those', or lastly you can rework the sentence so that it is a comparison that makes sense in the first place.
Let's look at the examples. So, the first sentence is flawed, it does not use comparisons logically. Let me show you why. Her prom dress was as glamorous as a movie star on the red carpet. First of, we know we're doing a comparison because of the phrase 'as glamorous as' and then let's look at what we're comparing. On the one hand we have 'her prom dress' that's a dress and on the other hand we have 'a movie star.' So, you probably don't actually don't want to compare your dress to a person, you either want to compare people to people or dresses to dresses. So the original sentence is flawed for this reason.
Let's look at the three ways to fix it, the three ways we just talked about. Method one, right here, is to compare apples-to-apples by repeating the apples. 'Her prom dress', that's our first apple, 'was as glamorous as the dress of a movie star.' So now we're comparing two dresses and that solves the problem. The second way I mentioned that we can fix the sentence, is by using an apostrophe s word, the word 'that' or the word 'those', that's the next example. Her prom dress was as glamorous as that of a movie star. So, 'that' of a movie star represents the dress of a movie star, and we have 'her prom dress' over here. Yet again, we fix the problem and the third method is demonstrated at the bottom, that's to rework the sentence entirely. Here we have, in her prom dress, 'she' was as glamorous as a 'movie' star' and now we're comparing a person to a movie star, two kinds of people, that's apples-to-apples and that fixes the problem.
Let's look at another example. Again, the first sentence is wrong and the three other sentences are going to exemplify the three methods of fixing logical comparison errors. Here goes. Compared to last week, this week's weather is far more mild. So we know we're dealing with comparison because of the phrase 'compared to' and here's what we're comparing. On the one hand we have 'last week' which is a period of time and on the other hand we have 'this week's weather' which is not a period of time, it's a kind of weather and that's not apples-to-apples, so three methods. First up, we can make it apples-to-apples by repeating the apples. Compared to 'last week's weather', 'this week's weather' is far more mild. Because I've repeated the apples, the comparison now works.
The second example, the 's, that or those method. In this case, we're going to use the 's method. Compared to 'last week's and that stands for last week's weather, 'This week's weather' is far more mild. Yet again we fix the problem.
The third method, reworking the sentence. The weather if far more mild 'this week' than 'last week' and now we're comparing two time periods so, we've solved the problem.
Another example. This one's a bit longer, but the same idea applies. Kentaro, an experienced sushi chef, claims that the taste of low-sodium soy sauce is not as good as regular soy sauce. Now, this is an example of a logical comparison that you might not notice if you weren't on the look out, but it is still wrong. Let's have a look. In the original sentence, where is the comparison? 'As good as' indicates a comparison. So on the one hand, we have the 'taste of low-sodium soy sauce' which is a kind of taste, and on the other hand, we have 'regular soy sauce', which is not a kind of taste, it's a kind of soy sauce. So, they're close but not quite there. We're comparing the taste of one thing to the actual substance of another, not quite right.
So there are three fixes, starting with number one. The first one is that we can make it apples and apples by repeating the apples. We have 'the taste of low-sodium soy sauce' and we have, here we are repeating our apples, 'the taste of regular soy sauce', that fixes the problem. Method two, the 's, that or those method is right below. 'The taste of low-sodium' soy sauce on the one hand is compared to 'that of regular soy sauce', and the word 'that of' represents the word taste. So we're good there and lastly we can rework the sentence. Kentaro, an experienced sushi chef claims that low-sodium soy sauce is not as good as regular soy sauce and here we've just stopped talking about taste and just started talking about 'regular soy sauce' versus 'low-sodium soy sauce.' So we've found another way to solve the problem of comparing apples-to-apples.
The last example and then we're done with this bit. Works by Thurber tend to be shorter than Vonnegut. So, this is a problem because, first of all, we do have a comparison, the word 'than' tells us that aut we're comparing two things that shouldn't be compared. We have 'works by Thurber' which is a collection of works or a collection of books, and 'Vonnegut' who's a person and we can't compare books to a person, not what we're going for. Method one is we can repeat the apples. So we have 'works by Thurber' and 'works by Vonnegut' solves the problem. Method two is the 's, that or those method. We have 'works by Thurber' on the one hand, and then we have 'those by Vonnegut' on the other hand and here we have to use the word 'those' instead of the word 'that' because 'that' only goes with singular things and 'those' goes with plural and 'those' refers to 'works' plural so it makes sense here to say 'those'. Method three, rework the sentence. Thurber tends to write shorter works than Vonnegut does and here we're comparing 'Thurber' and 'Vonnegut' so we're good. Now, that one is a pretty long lesson because this is the most important of all the comparison concepts but there are three more concepts and so let's go into number two of the four.
Comparatives and superlative, you need to be able to tell apart. Comparative is used to compare two things, superlative is used to compare three or more things. Let me show you what I mean. So, like I said, the comparative is used to compare two things, and in it's regular form it typically ends in 'er' ("smarter", "taller", "faster" whatever). Also, 'less' and 'more' can be used. For instance, ("less intelligent/more intelligent, more interesting" et cetera) There are some irregular forms they should be aware of right here, 'less, more, worse and better.' For instance, you wouldn't say something is good or you would say it's better and you wouldn't say it's badder, you would say it's worse. Anyway, here it is in action, the comparative. Renee is a better student than her brother, she goofs off less and studies harder and these are all the right words because we're using the comparative because there are two people, Renee and her brother, so we want to use the comparative form. 'Better', not 'best', 'less' not 'least' and 'harder' not 'hardest.'
Now, in contrast to comparative, we have superlative, which is for three or more things and the regular form is pretty similar to what we saw with comparative, but slightly different. In comparative, we had 'er' like if you were comparing two people, you might say one is 'smarter' or as a superlative, if you were comparing three or more people, you'd say someone was the 'smartest' and then instead of saying 'less' and 'more', you'd say 'least' and 'most' and yet again, there are some irregulars. Instead of saying 'less' and 'more', you'd say 'least' and 'most' and instead of saying 'worse' and 'better', you say 'worst' and 'best.' Now this is probably something you know intuitively and here's the example, it will probably sound obvious to you. Renee is the best student in her family, she goofs off least and studies hardest. But, it happens to be the case that on the SAT they give you hard examples. Let me show you what it might look like.
So, here we have an example that uses a comparative with the superlative, we'll get to that in a second, and it uses it correctly, so, we know we're dealing with superlative because of the ending 'est.' Now that should be a signal. Whenever you see a word ending 'er' or 'est' or whenever you see any of those irregulars, you should automatically check, is this being used properly. For instance, if it ends in 'er' it's comparative and we should only be comparing two things. If it ends in 'est', it's superlative and it should be comparing three or more things. This one's right because we say I see '-est', that means it's superlative, let me check if we're comparing a lot of things and sure enough we are, of all the people. So there are plenty of people being compared and this is correct.
But let me show you an example where comparative and superlative is not used properly. If forced to compare the lyrics of Kanye West with those of Britney Spears, I'd say Kanye's are the best. Now you may think that Kanye's are the best overall but that's not consistent with what's going on in the sentence. We see the word best and that should be a superlative which means it's out of three or more things or people being compared. But in the sentence only two people are being compared. We have our friend Kanye and our girl pal Britney, so because there are only two things being compared, we need a word like better. So be on the lookout whenever you see one of those comparatives or superlatives, usually '-er' or '-est'.
Next rule, don't compare something to a group it's part of without including "other" or "else". Now that sounds a little vague without examples so let's look, this won't be complicated. In my opinion, In-N-Out cuisine is tastier than any fast food you can find. Now the sentiment is clear but the grammar is wrong, here's why. In-N-Out can't be tastier than any fast food because it's not a fast food. What you really want to say is that In-N-Out is tastier than any other fast food you can find, if that's what you believe.
So similarly, because she has been working for the company the longest, Michaela makes more money than anyone employed there. That doesn't make sense because she is employed there so how can she make more money than anyone employed there? That would mean she makes more money than herself? It doesn't make sense, so yet again we have to insert a word, anyone else employed there and the last principle, be clear what you're comparing. So when you make a comparison you have to make sure that it can't be interpreted in more than one way. This will probably look familiar when you see it, here it goes. Gwen gets better grades when she studies with Tanya than Max. I think you can probably tell that can be interpreted two ways and here they are. We could take it to mean that Gwen gets better grades when she studies with Tanya than when she studies with Max or we could take it to mean, Gwen gets better grades when she studies with Tanya, than Max does. So if this were the sentence you originally got on the SAT, you'd want to look for an answer choice that clarified what was going on. With those four principles in mind, let's check out a sample SAT problem.
So here we are with an SAT question you might expect to see on the identifying errors portion of the test. Now to recap, what we're going to do is read through the sentence and see if an error jumps out at us. If so, great, we're going to circle it because that's the answer we're going to say is the answer. If not, we'll go through one by one, piece by piece, looking for the answer that's flawed. Here it goes. Although Des Moines is the cheaper of the two destinations, Maui's climate is distinctly more appealing than Iowa or no error.
Now I'm not sure if it jumped out at you, but let me tell you what the right answer is and it's the right answer because it's wrong in the sentence and now we'll look at the other pieces of the sentence and go over what might have gone wrong or what you should be on the lookout for. So the answer we're going to choose is Iowa. Here's why. We're making a comparison with words like more than, so we need to make sure that the pieces being compared are apples-to-apples and they're not. Here we're comparing Maui's climate to plain old Iowa. We can't compare a climate to a place so actually not that we have to tell the test writers what we think that the sentence should say but it should say, just for reference, Iowa's or Iowa's climate, something like that, then we'd have an apples-to-apples comparison. Let's just go through the other pieces of the sentence, starting with A.
Although, is a contrast word so you want to make sure the two parts of the sentence contrast and sure enough you're saying, on the one hand, here's a benefit to Des Moines, on the other hand here's a benefit to Maui. So that's a contrast so 'although' makes sense. 'The cheaper of' might sound a little funny to you but it's correct. It's one of these '-er' words, that means it's comparative and we need to make sure we're comparing two things. Sure enough we are, Maui as a destination and Iowa as a destination so that's good and distinctly more appealing. Some people might choose this because it sounds weird to them because distinctly it's not a word they use in everyday life but there's nothing grammatically wrong with it or stylistically wrong with it so it's fine and that's why D is the right answer. So with that in mind let's do a bottom line recap.
So in summary there are four principles to watch out for when it comes to logical comparison. The first one and the one that's most important and that it comes up most frequently on the SAT is that you have to compare equivalent concepts. That's the apples-to-apples one and to recap, there were three ways to fix that. First of all you could add apples to the sentence so that you had apples over here and apples over there.
The second thing was that you could use an apostrophe 's' word, the word 'that' or the word 'those', and the third way to fix the issue was to just read where the sentence overall. The second principle was that you have to use comparative or superlative correctly. To recap that one, if you see an '-er' word, then you need to make sure you're comparing two things. If you see an '-est' word, make sure you're comparing three or more things.
Next, don't compare something to a group it's part of without including the word else or other and lastly, be clear what you're comparing. If you can't tell whether she studied more with Max than Tanya did or more with Max than with Tanya, you need to look for an answer choice that rewards that in a way that makes the meaning clear and that's everything you need to know about logical comparisons.