Is it worth studying fallacies for the LSAT?

Answer 1

It is helpful to know which kinds of flawed reasoning is used by the test writers over and over again. Identifying these flaws as you read can help you avoid trap answers and predict correct answers for certain question types. Learning the flaws by reading them off a list and memorizing them is unhelpful in my opinion. Test writers can craft the answers to Flaw question types with various levels of descriptiveness. For example, an argument might be flawed for confusing sufficient for necessary, and the correct answer may say just that, or instead the correct answer may illustrate what confusing sufficiency for necessity means in that context. Therefore, practicing with real LSAT questions and thorough review exploring why the correct answer is correct and why the incorrect answers are incorrect is the best way to learn Flaw question types, and all other question types for that matter.

Answer 2

Fallacies are only relevant to flaw questions in logical reasoning. My experience has been that those who have studied formal logic (including fallacies) tend to over analyze LSAT questions, wasting time. The main challenge for most people with flaw questions is learning the vocabulary that LSAC uses on the test to describe the errors in logic. Consequently, you won't need to study fallacies to do well on the LSAT. Just be sure that you learn what the answers mean.