When it comes to the LSAT, there’s nothing more important than knowing the common LSAT fallacies cold. Here’s how to make your flaw(ed) life easier.
1. Why LSAT Fallacies Are Important
The fallacies you’ll encounter on the LSAT play a key role in several important Logical Reasoning questions and Reading Comprehension passages.
Clearly, you’ll need to know the fallacies for any Flaw question. But you’ll also need to know your LSAT flaws for Weaken, Strengthen, Necessary, Sufficient, and even some Describe questions. That’s about two dozen questions on any given LSAT, spread over two LR sections.
Also, most Reading Comp passages have more than one viewpoint; in many of these passages, one viewpoint will point out a flaw in the other viewpoint’s reasoning. Knowing your fallacies can help you understand some difficult passages.
2. You Need to Memorize the Common LSAT Fallacies
Since the LSAT is a test of skill and not regurgitation, there are only a few things you need to memorize to help you do better on the test. But knowing a list of the common fallacies is definitely something that can help you do better on the test. So don’t miss out on memorizing the LSAT fallacies.
You need to memorize a short description of the fallacy—the wording does not matter if your description is accurate. You also need to memorize a quick example of the fallacy, one that’s hopefully intuitive. Here’s an example:
Ad Hominem fallacy: Attacking the source of the argument and not the argument itself.
Example: Donald Trump claiming he lost an argument because the judge was Mexican.
3. A Couple of Memory Tools
Memorizing the LSAT fallacies is a lot easier than most people expect it to be. I memorized the flaws by using a “memory palace.” The technique involves associating each flaw with an image and a location in a familiar place or building, like your house. I created an image representing a fallacy in every room, hallway, and stairs at my parents’ house. I would imagine myself walking through the house and seeing these images and then I would recall the relevant fallacy, its description, and an example.
For example, when I walk into my parents’ house, the laundry room is on the right. I look inside the washer and I see a horizontal line across the washer door and two Ps spinning around going above and below the line. That’s my image for Circular Reasoning—the premise (P) and the conclusion are interchangeable; they play the same roles in the argument both above and below the “implication” line. Is it a perfect image? Heck no, but it works well enough. Don’t be intimated by having to create images. They don’t need to be ingenious, they just have to work for you.
You can read more about memory palaces online, and there’s a great Ted Talk to boot.
Another memory technique you can use involves an app called Anki. Anki is used mostly by language learners and med students to memorize thousands of vocabulary words and scientific or mathematical concepts. Anki is a “spaced repetition system” or SRS, which means that the app will make you review something you learned for today, tomorrow, then three days from tomorrow, then a week from then, and so on. This way, you’re forced to recall something just before you forget it.
Anki is a bit clunky and hard to learn though, but for some people it may work out really well.
4. Apply, Apply, Apply
Memorizing the fallacies is necessary, but not sufficient, for LSAT success. You’ll need to know how to apply the flaws to any number of novel examples. This is easier to practice than you might think. Arguments are all around us, and flawed arguments are by far the rule and not the exception. Essentially, only logicians and mathematicians make valid arguments. Pretty much everyone else engages in some form of flawed reasoning, even if that just means leaving assumptions unsaid.
Your favorite TV show is ripe for flawed reasoning analysis—reality TV works really well. Your favorite (or least favorite) “news entertainment” channel will give you endless opportunities to apply your LSAT fallacy knowledge. Sportscasters and politicians on both sides of the aisle are also in the business of peddling flawed arguments.
So get out there and get after those LSAT flaws. But don’t for a moment think you can get through it without memorizing them.