Inference Strategies

[kggaines]

MR. Killoran,
My question deals with the three strategies for making inferences on pages 74-80 of the 2015 logic games bible. I was just wondering what the relationship is between the three strategies and whether they overlap. It seems as though linkage and rule combination are mutually exclusive, since one involves a rule in common and the other doesn't, but it also seems like the restrictions strategy could incorporate elements of both linkage and rule combination depending on the point of restriction you are examining. Is it possible to have a restriction that involves neither a linkage nor a rule combination?

The reason I ask this question is because the example you provide for rule combinations on page 76 also seems like a restriction to me. Since O is in slot 5 it prevents K or L from being placed in slot 6, and then a triple option results. I'm curious as to how this differs from the "Not Law Restrictions" discussion on the following page (77).

Sorry if my question has gotten a little convoluted, I'm just trying to keep the three concepts straight in my head and put my finger on the precise relationship/overlap between the three strategies.

Thanks!

[Dave Killoran]

Hi K,

Thanks for the question! One thing about logic, and really learning in general, is that in almost all cases, things can be combined or flow together. And that's true in this section as well. What I've done in these pages is to isolate what I consider to be basic processes in making inferences. But, that doesn't mean they have to operate in a wholly separate channel from any other similar process. Sometimes they do, but sometimes they cross over and combine with the others! And in fact, the more they combine, the more frequently you begin to see deeper and more powerful inferences. So, what you've noticed is indeed occurring, and the fact that you noticed it is excellent The ability to recognize when ideas have been combined on the LSAT is an important one, and it will help you to better understand how the test makers think.

The above might raise the natural question of why I separate them out. I do that because these are the basic building blocks of this important process, and when you isolate them, it makes them easier to understand. Its kind of like building a house—if you know all the building materials at your disposal, you can look at any house and have a better sense of how it was built and how things work. In this case, now that we've isolated these ideas, if you see any single one of them, that can start the inference process. And, if other elements combine with that process, it's just fine, and to be expected.

So, great job on understanding that point! Please let me know if that helps. Thanks!

[kggaines]

Yes sir, makes perfect sense, I think I was overthinking it a little. Thanks for your time!

[Dave Killoran]

No problem, glad I could help! Better to ask about it and know exactly what's happening, than to wonder about it, so I'm glad you posted your question. If you run into anything else that isn't clear, please let me know. I'd be happy to help out

Thanks!