What the LSAT Tests — And Why

In some sense, the first half of the title question is self-evident. The LSAT tests basic skills on each section. On the Logical Reasoning, the LSAT tests the analysis of arguments. On the Analytical Reasoning (i.e. the Logic Games), the LSAT tests the ability to make deductions from a collection of logical conditions. On the Reading Comprehension, the exam obviously tests how deeply one understands what one reads. On the Writing Sample, the LSAT obviously tests your writing ability. This is not much of a surprise to anyone who has more than a passing acquaintance with the LSAT.
As you also probably know, when you sit for your real LSAT, there will be five 35-minute multiple-choice sections followed by the Writing Sample. Four of the five sections will count for your score, and these always include two Logical Reasoning sections, one Analytical Reasoning section, and one Reading Comprehension section. This means there will be one multiple choice, any of those three formats, that doesn’t count for your score, the so-called “experimental section.” Of course, by the time you get to that second Logic Games section or that third Logical Reasoning section, you will know that one of the sections of that kind has been experimental, but you have no way of knowing whether it’s the one you are facing now or one you already finished! The LSAT designs things so that you always have to treat the section in front of you as the real thing.  Why on earth does the LSAT force you to do something that doesn’t count?
Believe it or not, it is not simply because the LSAT is sadistic. Here, we have to step for a moment, in the world of the test writer. I write test questions for a living. When I write a question, I may think it’s a good question, but how do I know? I need data. Sometimes, I write what I think is a good question, but then high performers get it wrong for understandable reasons and/or low performers get it correct for the wrong reasons! That’s not a good question, and only data will demonstrate this. All the questions that count on your current LSAT were once on the experimental sections of earlier generations of LSAT takers, and the data gathered in those trials validated the questions that wound up being used. Just as these earlier LSAT provided the data that makes your LSAT a statistically sound test, so you provide this same service for future LSAT takers. It’s an altruistic social-contract thing — except that, if you are taking the LSAT, you really have no choice about participating.  
WHY THESE QUESTIONS?
OK, of the sections that actually will count toward your LSAT score, why does the exam ask what it asks? First, let’s start with the Logical Reasoning questions, which account for 50% of the LSAT score. Clearly, if you don’t like analyzing arguments, you have no business becoming a lawyer! Wait! Let’s make that into an argument. Proposition #1: “If an individual is qualified to be a lawyer, then this individual is skilled in analyzing arguments.” Proposition #2: “Person A is not skilled in analyzing arguments.” What can we deduce? Using modus tollens logic (i.e. a classical way to talk about a deduction directly from the contrapositive), we see that Person A is clearly not qualified to be a lawyer! Of course, all this should not be surprising to anyone familiar with the LSAT: of course, lawyers should be good at arguments and of course the LSAT should test this! I would simply suggest the larger view: at one level, skill in arguments is about winning, but the strongest arguments determine not only real financial and legal consequences affecting people and institutions but also the laws that govern our land. Arguments shape the law, and the law shapes our lives. This is no unimportant matter.
Reading Comprehension tests reading ability. Do you have any idea how much you are going to have to read and analyze when you are in law school — and when you are practicing law? Furthermore, when you are lawyer, you don’t get to read only what you want to read or only what you find interesting. Many times, you may have to gather important background on a matter from sources you find less than scintillating: in fact, how enjoyable you find the reading is absolutely uncorrelated with how important it will be for your work. A diligent lawyer gets the information she needs from reading, irrespective of the accessibility of the source.  
The Reading Comprehension and the Writing Sample have something else in common. Imagine being a lawyer 150 years ago, say a country lawyer such as the young Abe Lincoln. This country lawyer probably could meet face-to-face with just about everyone relevant to his cases. By contrast, in our modern multinational world of 7 billion people, there will be countless times in your career that you will send important information to, or get it from, someone you never will meet face-to-face. So many people will encounter you only through your words: your emails, your briefs, your publications, etc.; similarly, words may be your sole experience of some other people. You only get one chance in this life to make a first impression on anyone. This is precisely why it’s critically important that everything you put into written words reflects your very best, and that you get the most of everything you need to read. This is precisely why the LSAT tests reading and writing.
LOGICALLY SPEAKING
Finally, Logic Games. Once again, LSAC did not concoct this purely to make you miserable: it’s not the “mind games” section! Think about it this way: Sometimes in a project or case, all the information you need comes in one place. Both Logical Reasoning and Reading Comprehension have this quality: here’s all the info you need, now do X with it. Many times in the messy real world, though, the vital information is not all in one place. In fact, many times, say in criminal cases, it may be that there’s a pattern of vastly different kinds of information from a wide variety of places, and the lawyer has to assemble this disparate information into cogent argument for a quite specific conclusion. That’s beginning to sound much more like the LSAT Logic Games!  
One underappreciated fact about this section is that there are tried-and-true strategies that can enormously simplify the Logic Games, so much so that some students can connect with the satisfying play aspect of the “game.” Just as some people do crossword puzzles or Sudoku for fun, so people who gain sufficient skills in Logic Games find them similarly enjoyable and rewarding.  

Author Mike McGarry of Magoosh