How to Destroy Arguments on the LSAT

This article will focus on Logical Reasoning questions that involve arguments. But keep in mind that not all passages are arguments! For a refresher on what makes a passage an argument, click here.

Step 0: Start with the Passage

When you’re faced with an argument on Logical Reasoning, the worst thing you can do is skim through it, passively accept its conclusion, and jump straight to the question and answer choices. Similarly, reading the question first before the passage sets us up for failure, full stop. 

Thinking like a lawyer starts here, on your LSAT journey. LR tests our ability to push back against faulty reasoning by identifying logical flaws.  Follow these next steps for the most efficient, effective way to do that.

Step 1: Accept the Premises

We tend to see two types of arguments on the LSAT: valid and invalid. The  test will throw all sorts of invalid arguments at us  -  with leaps in logic,  straight-up incorrect claims, and conclusions that go way too far. Which claims should we object to, and which do  we accept as true?

Put simply,  our job is to accept the argument’s premises, but attack its conclusion. (If you’re shaky on the difference between premises and conclusion, read more here.) 

Even if a premise is false in the real world,  we need to remember that we’re operating in LSAT-land, where premises are treated as facts for the sake of argument. For example, If an argument says, “Everyone named Benjamin is super nice,” nobody cares whether you know a Benjamin who’s a real jerk. You’re operating on a plane of logic where, for the sake of the argument, it’s a fact that all Benjamins are super nice. Accept this and move on. Trying to argue with the given facts of the argument will only waste your own time. 

Step 2: Identify the Conclusion

We’ve accepted the evidence as true. Now what?

To continue the example above, let’s say the argument goes on to say that “Steve is super nice, so Steve’s middle name must be Benjamin.” This sentence contains another premise (that Steve is super nice) and a conclusion (that Steve’s middle name must be Benjamin).

The alarm bells should already be ringing in your head - this is what we want to be arguing with. 

Step 3: Evaluate the Conclusion

We know the facts, we know the conclusion - now we decide whether the argument is valid or invalid, and why.

While,  in LSAT-land, we must accept stated facts as facts (don’t try to argue that your friend Benjamin is mean, or that Steve is mean), we don’t have to accept the conclusion as a fact.

Although all arguments, by definition,  have conclusions, not all arguments prove their conclusions. Learn to spot the difference between valid and invalid arguments. A valid argument proves its conclusion soundly, while an invalid argument does not. 

Anytime you hear a conclusion on the LSAT, pause to evaluate its validity. Figure out whether the author has proven what they set out to prove. Critically engage with every argument you encounter on the LSAT.

Always Push Back Against Flawed Arguments

Most conclusions on Logical Reasoning are unwarranted—in other words, most arguments are invalid, or flawed, in some way. Your job is to identify these flaws and argue back. 

A lawyer doesn’t let the opposing counsel get away with making bad arguments in court. Likewise, you cannot allow authors to get away with making flawed arguments on the LSAT. Don’t passively accept whatever the test throws at you, no matter how reasonable or agreeable it seems. Instead, engage with it as if you were in a debate with an opponent - find the weak spots, and push back against anything that isn’t 100% proven by the premises.

In the example above, the author concludes that “Steve’s middle name must be Benjamin.” But hold on a second—do the premises prove that Steve’s middle name must be Benjamin? No. The premises say that if someone’s name is Benjamin, they must be a super nice. But that doesn’t mean that everyone who’s super nice must be named Benjamin. That’s the disconnect.

There could be other ways to be super nice that don’t involve being named Benjamin. In other words, the author hasn’t proven that being named Benjamin is necessary for being super nice. The conclusion is unjustified.

The analysis above is what it looks like to critically engage with a flawed argument.

The only way to get better at identifying flawed arguments and cracking them open is to practice yourself. Start drilling Logical Reasoning Questions.