Contrapositive supplement

[nelson3clan]

Is there a online supplemental section on contrapositives?

Carole

[Dave Killoran]

Hi Carole,

Thanks for the question. There isn't a specific extra section on just contrapositives, but that's because they come up in almost every discussion of conditional reasoning. Is there something specific we can help with about the concept though? We're happy to help out

Thanks!

[nelson3clan]

Hello Dave,
I went back to the Logical Reasoning Bible Chapter six on Conditional Reasoning. I was having a conflicting time with some of the questions on contrapositives and negations were concerned. The except and unless ones were not being properly handled by me. I was negating but not flipping or something. Then I flipped and negated. It was just weird. It is like the closer the 8th gets the more mistakes I'm making. YIKES!! God know's I don't have time to redo the entire book again. Somedays it's like a light bulb comes on other days, like today, it feels like all new material!!!

Carole

[Dave Killoran]

Hi Carole,

That can happen, so don't feel frustrated! When you are trying to absorb this much material, some days your brain just wants a vacation. This is probably one of those days

Let me make some comments about conditional reasoning that might help you out. Over time, you'll start to instantly see the conditional relationships when they are present. In the same way I see a "Yield" sign when driving and know to look for other cars in the vicinity, the various conditional statements become familiar over time and you immediately know how to handle them (it's harder for statements featuring trickier words like "unless" or "except," but still achievable).

Once you know the conditional relationship in play, all the variations on that are like shadows that are always present. With the contrapositive, it's ever-present, and it's always the same: reverse and negate. So, it's like a twin that is always there, unchanging.

With Mistaken Negations and Mistaken Reversals, the same thing is true, but in these two cases I don't worry about them unless they appear. Then I know something is up and that will require closer examination.

I've said in many posts that tracking conditionality is like being an air traffic controller. I don't worry about it until it appears on the radar, and then, I only worry about what I need in the context of the problem (as in knowing that the CP is always valid, and that the MR and MN is invalid, etc). In other words, you don't have to think about it constantly; only when it is there. So, first learn how to diagram sentences. then learn what the CP, MR, and MN look like, and then only use what you need when you need it.

For more reading on conditionality, check out this post I wrote in response to another student: http://forum.powerscore.com/lsat/viewto ... 569#p18569

Those are brief thoughts, but perhaps they will set you at ease a bit. Thanks!