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Stop what you’re doing (in Logical Reasoning), because I’m about to ruin (your incorrect approach)

Sorry not sorry for the post title.

Anyhow, logical reasoning. Half of every LSATPrep test. How should you approach it?

Well, here’s the approach you should stop: read through the stimulus quickly, pick the answer choice that seems the best, and move on.

Why? Because logical reasoning presents arguments, not articles. So, you have to read logical reasoning like an argument.

If you read an argument, you don’t read it from top to bottom. That might be the order it’s presented in, but the order of the argument is different. It goes: premise, reasoning, conclusion.

For instance, literally the world’s most classic argument:

All men are mortal.

Because Socrates is a man,

therefore Socrates is mortal.

Arguments go wrong when a piece is missing, or, more subtly, when one piece doesn’t actually quite lead to another. For instance, your reasoning might not actually lead to your conclusion:

All men are mortal.

Because Socrates is mortal,

therefore Socrates is a man.

(See what I did there? Mixed up the necessary and sufficient conditions, I did.)

How do we apply this to the LSAT? Well, let’s take a real LSAT question, like sample test question 23 section 2. Paraphrasing, it goes:

Philosopher: Morally ok actions are those that probably make people better. Morally wrong actions are only those that probably make people worse. Therefore, an action which doesn’t make people better or worse is probably morally ok.

Now, the question asks us what the assumption is. It’s easy to see something’s strange with the argument, but we’re going to waste a lot of time if we just jump to the answers and try to figure out what’s strange from there. Let’s put this in terms of a proper argument first.

Premise: the first two sentences.

Reasoning: ?

Conclusion: the last sentence.

Well, that’s what’s strange with the argument. They’re missing reasoning! I don’t see anything in the premises about actions that don’t make people better or worse. We’d need to make a statement of reasoning that links the premises and the conclusion (aka an assumption).

It’d probably look something like:

Premise: Morally wrong actions are only those that probably make people worse.

Reasoning: Because an action can only be morally wrong or morally ok.

Conslusion: Therefore, an action that’s not morally wrong is morally ok.

And that’s pretty much the answer, and also a good way to make the word “morally” look really weird.

So, what’s the overall lesson for logical reasoning?

Always put the stimulus in the form of premise, reasoning, conclusion before going to the answer choices. If anything is missing, make a note of it, as that’s probably going to be key for the answer.

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