What are levels of truth on the LSAT?

Levels of truth apply most directly to inference questions on the Logical Reasoning section, but in truth, they are universal on the Law School Admission Test (LSAT). At its most basic, a level of truth is just how true something is. Which means it applies everywhere. Much of the test is about describing how true answer choices are!

There are three levels of truth an argument (or, really, anything) can have:

• Must be true

• Could be true / could be false (these are synonymous)

• Must be false

(Really, they’re just true, unknown, and false. But the LSAT likes its complex language, so instead we have the above.) And to tie these definitions into other terms that are omnipresent on the LSAT, a flaw does not mean something must be false, only that it could be false (or could be true).

Everything told to you within a passage is true, but that doesn’t mean everything told to you within the answer choices has to be true. In fact, in many question types, some answer choices are true, some are false, and some are unknown (could be true / could be false). Identifying which is which is a very important skill. In fact, that’s the entirety of inference questions. An inference, or a deduction, is an additional component that is proven directly or indirectly by a passage. Let's give a very basic example.

The only foods being served at this barbecue are hotdogs and hamburgers. John will eat food, but he will not eat a hotdog.

It's clear, in this circumstance, that John will be eating a hamburger. It's not said explicitly, but it has to be true if all the information given above is true. Thus the fact that John will be eating a hamburger is an inference, or a deduction, of the above passage.

An inference question could ask you about any component of truth. And the level of truth can be disguised. For example, the prompt could ask you to identify what “must be true except,” which would be synonymous with asking what could be false. There are plenty of variations, including “most supported by” but your approach doesn’t change regardless. Any inference question can only ask you to find one of those three levels of truth.

Side Skill: Making Level-of-Truth Inferences

Those levels of truth apply to deductions that you can make from the information given to you within a passage. Let’s give some examples. Here is a sample passage, and then we’ll give levels of truth to a number of following statements. (And note: inference passages do not have conclusions or arguments, simply piles of facts that generally interlink.)

I own precisely six articles of clothing. Four are shirts, and two of those shirts are red. I own at least two blue articles of clothing. I own one pair of socks. One article of clothing I own is yellow. 

Now some sample statements, to which we’ll apply levels of truth:

• I own one pair of yellow socks. 

• I own three blue shirts. 

• I own an elephant. 

• I own 10,000 elephants.

• I own fewer than two purple articles of clothing. 

  
  

These all have a level of truth attached. Some are proven true by the passage, some are proven false, and some are not proven at all -- in that they could be true or false. 

• I own one pair of yellow socks -- this could be true or could be false. We have no evidence either way. 

  
  

• I own three blue shirts -- this is definitely false. I only own four shirts, and two are red, which means the maximum number of blue shirts I could have is two, not three. 

  
  

• I own an elephant -- this could be true or could be false. We have no evidence either way. 

  
  

• I own 10,000 elephants -- this could be true or could be false. We have no evidence either way. 

  
  

• I own fewer than two purple articles of clothing -- this must be true. There are six items of clothing, and five colours are accounted for. (Two red, two blue, and one yellow.) Which means the maximum for other colours is one. Thus fewer than two.