The Basics of "Some"

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As we gear up our LSAT preparation again for the September LSAT, I thought we could brush up on our quantity statement techniques. There are two types of quantity statements: “some” and “most.” Today, I want to go over the former.

In our world of LSAT prep, “some” means “at least one.” Often you will run into a “some” statement and the word “some” will not be present. But, you will know that it is a “some” statement because the meaning of the quantity word or phrase will be “at least one.”

For instance, all of the following statements constitute “some” statements. The quantity word or phrase that helps point out that it is a “some” statement is bolded.

(1) Often, people in this district ride their bikes to work

(2) Sandra will sometimes eat peanut butter.

(3) Many of the people who took Chemistry also took Biology.

(4) There is at least one person in Mr. Kubrick’s class that has a nut allergy.

(5) Half of those in Econ 101 also speak fluent French.

All the words and phrases in bold mean “at least one.” Some make arguments that “often” and “many” fall under the “most” quantity category. But, while “often” and “many” could be considered “most,” i.e. greater than 50%, they will always be considered “some.” Thus, we equate “often” and “many” with “some.” A lot of students also get nervous around considering “half” a “some” quantity word. “Most” statements refer to “more than half.” Thus, “half” is considered a “some” statement.

Now let’s try to diagram the following example:

 “Some people who like strawberries are allergic to eggs.”

LS-some-AE

 It’s important to note that “some” statements, unlike Sufficient & Necessary (S&N) statements, do not have contrapositives. We can, however, switch the left and right-hand-side variable without negating, like so:

 AE-some-LS

This reads: “Some people who are allergic to eggs like strawberries.”

Now, what can we “combine” a “some” statement with? We can never combine a “some” statement with another “some” statement. Likewise, we can never combine a “some” statement with a “most” statement. We can only ever combine a “some” statement with a S&N statement. This occurs when the right-hand-side variable of a “some” statement is the same as the sufficient condition of a S&N statement.

For example:

Some people who like strawberries are allergic to eggs. Everyone who likes strawberries also likes blueberries.

 We will diagram like so:

 LS-some-AE

AE-some-LS

LS ==> LB

not LB ==> not LS

We can take the second form of the quantity statement and combine it with the S&N statement like so:

 AE-some-LS ==> LB

 We can, therefore, conclude: “Some people who are allergic to eggs like blueberries.”

 AE-some-LB

 Easy, right? Now go one and try practicing some Logical Reasoning sections with “some” statements in them. I will make sure to revisit this concept with you in a few weeks to make sure we’ve really gotten the hang of it!

Happy Studying!

Updated on Aug 18, 2016