PTB.S1.Q23

dictronic110

My understanding seems to be different with the explanation on the Manhattan forum. Just want to make sure I understand this Q.

The premise says deep tillage is more harmful than no-till. The conclusion says farmers who use deep tillage should incorporate no-till methods instead. My understanding is that the author is suggesting famers to use deep tillage+ no-till methods. If so, negating the answer choice C would wreck the argument: if other methods other than deep tillage are also variable, the farmers could just replace the deep tillage method completely, rather than combining deep tillage with other methods.

Is that correct? Thank a lot!

David Wayne

First off, i thought this was an incredibly difficult question when i first did it.

C is right because the argument's evidence does not necessarily establish that no-till methods are the most logically supported alternative. Deep tillage is ruled out, but the error committed by this flawed argument falls into the category of the fallacy of intermediate possibilities. Two extremes are identified, one is noted as falling short of an objective, and the option at the other end of the spectrum is prescribed without consideration of a middle ground option. C ensures that no alternative in between is logically supported by the information presented about farming techniques. Enormous levels of difficulty are presented in this argument through the use of foreign subject matter, obscuring this fallacy from being readily discernible. You'll see it a couple of times though if you do most of the preptests. Questions like these illustrate the fact that strengthen/weaken/necessary assumption question can be flawed in as severe a manner as flaw/descriptive weakening questions.

Also, i don't see where you identified anything about combining methods. The stimulus's last sentence says that they should incorporate these new methods INSTEAD.

dictronic110

Thanks for the response. Your analysis makes a lot of sense. But I think I have a problem with C. From my understanding, C means only deep tillage is viable. But the conclusion says famers should use no-till method to replace deep tillage. How can that happen when only deep tillage is viable? Maybe I misunderstood what C is saying or the relationship between no-till method and deep tillage method. Please point it out. Thanks a lot!

David Wayne

Sorry for the late response.

You need to read the stimulus more carefully (sorry if that sounds obnoxious!)

The farmers' purpose is to incorporate aeration techniques, and tillage is one method of doing so. The last sentence argues that the farmers should use other topsoil aeration techniques because deep tillage is problematic. The argument's attempt to rule out tillage completely is incomplete because other types of tillage are not addressed - an assumption fixed up by answer choice C.

You have understood answer choice C to mean that tillage is the only means available to farmers to aerate their soil. What C really means is that there is only one type of tillage viable for this purpose: Deep tillage. With that ruled out, it is more clear that no-till methods of aeration are preferable. Again, read the last sentence very carefully. Tillage is one of at least two options (the other including no-till methods) that are at the disposal of farmers interested in aerating their soil. C's stipulation is that deep tillage is the only appropriate tillage method, not the only appropriate aeration technique, so no-till methods are still viable even with this assumption. I think that the foreign subject matter really complicates this problem. Is that clear?

dictronic110

Thanks! You're absolutely right. The LSAT boils down to whether you can identify the logic from convoluted English and the foreign subject matter, rather whether you "know" the logic.

I think the argument is saying because deep tillage is bad, no tillage should be used at all. But what about medium tillage? easy tillage? C blocks those possibilities.

From your response, I assume you've gone through the Trainer? I think looking at the subjective LR questions from the "flaw lens" quite helpful. Typically I know what to look for before diving into the answer choices and more importantly, stay on the argument.

I appreciate your response!