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 wwarui
  • Posts: 32
  • Joined: Nov 13, 2011
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#13254
Hello,

Stimulus: "Obviously, we cannot in any real sense mistreat plants. Plants do not have nervous systems, and having a nervous system is necessary to experience pain."

Please illustrate these SN statements.

Here is what I did:

Not Nervous System therefore not Mistreat Plants
Contrapositive: Mistreat Plants therefore Nervous System

Experience Pain therefore Nervous System.

Combine 'rogue infor' i.e., Experience Pain therefore Mistreat Plants.

BUT my reasoning does not make sense. According to my logic, the rogue infor is sufficient condition in both statements. Problem: how do I decide that Experience Pain is the sufficient condition of Mistreat Plants? Cannot answer this, hence need help.


Thank you.
 Steve Stein
PowerScore Staff
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#13258
Hi,

In that one, the first sentence is the conclusion, and two premises comprise the second sentence.

Plants do not have nervous systems:

..... Plant :arrow: nervous system.

A nervous system is necessary to experience pain:

..... able to experience pain :arrow: nervous system

Contrapositive:

nervous system :arrow: able to experience pain

Thus:

Plant :arrow: nervous system :arrow: able to experience pain

Conclusion:

Plant :arrow: able to be mistreated

So the author must believe that if something is unable to experience pain, it cannot be mistreated:

able to experience pain :arrow: able to be mistreated

-this is the link that would justify the author's conclusion.

The contrapositive would dictate that to be capable of being mistreated, an organism must be able to experience pain:

able to be mistreated :arrow: able to experience pain

I hope that's helpful! Please let me know whether this is clear--thanks!

~Steve
 wwarui
  • Posts: 32
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#13262
Hi Steve,

Yes, this is clear.
Thank you so very much.
 smile22
  • Posts: 135
  • Joined: Jan 05, 2014
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#14310
I answered this question correctly; however, I was torn between answer A and D. It appears that the only difference between these answer choices is in how they are introduced. Answer A is introduced with the term "any" and answer D is introduced with the term "only". Would answer A be an assumption? I am thinking that perhaps the term "any" makes this answer more minimalistic as opposed to answer D.
 Steve Stein
PowerScore Staff
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#14325
Hi smile,

That is correct--the words "any" and "only" make those very different claims. Answer choice(A) says basically that if you can experience pain, you can be mistreated:

able to experience pain :arrow: capable of being mistreated

Answer choice (D) on the other hand, says that only those organisms that can experience pain can be mistreated. In other words, if we know that an organism can be mistreated, we know that it must be able to experience pain:

capable of being mistreated :arrow: able to experience pain

I hope that's helpful! Please let me know whether this is clear--some conditional reasoning can be quite challenging--thanks!

~Steve
 smile22
  • Posts: 135
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#14332
Thank you for your reply!
 srcline@noctrl.edu
  • Posts: 243
  • Joined: Oct 16, 2015
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#23255
Hello Steve

This question is causing me to experience pain.....

How is the "Plants do not have nervous systems a conditional statement. This seems to mean that its part of the premise and the sentences after are the conditional statements. Can you please explain this?

Also here is my diagram:

IF experience pain :arrow: must have nervous system
(+) if plants dont have nsystem :arrow: cant exp. pain

conclusion: we cant mistreat plants.

Thankyou
Sarah
 Robert Carroll
PowerScore Staff
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#23303
Sarah,

If plants do not have nervous systems, then being a plant is sufficient to prove that the lack of a nervous system is necessary. Thus:

plant :arrow: nervous system

You're correct about the other conditional:

experience pain :arrow: nervous system

and its contrapositive:

nervous system :arrow: experience pain

The conclusion says:

plant :arrow: able to be mistreated

The connection that needs to be made is between experiencing pain and mistreatment. Specifically, we have this so far:

plant :arrow: nervous system :arrow: experience pain

If the following could be added:

experience pain :arrow: able to be mistreated

Then the whole conditional would be:

plant :arrow: nervous system :arrow: experience pain :arrow: able to be mistreated

And the summary of the chain is:

plant :arrow: able to be mistreated

Thus, the gap-closing missing information is:

experience pain :arrow: able to be mistreated

In other words, if something cannot experience pain, then it cannot be mistreated. The contrapositive: if something can be mistreated, it must be able to experience pain. That is what answer choice (D) says.

Robert Carroll
 LSATer
  • Posts: 47
  • Joined: Nov 13, 2016
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#33294
Hi Steve,

Although, I understand the difference between A and D, I don't understand what makes D better than A. Can you please help here?

LSATer


Steve Stein wrote:Hi smile,

That is correct--the words "any" and "only" make those very different claims. Answer choice(A) says basically that if you can experience pain, you can be mistreated:

able to experience pain :arrow: capable of being mistreated

Answer choice (D) on the other hand, says that only those organisms that can experience pain can be mistreated. In other words, if we know that an organism can be mistreated, we know that it must be able to experience pain:

capable of being mistreated :arrow: able to experience pain

I hope that's helpful! Please let me know whether this is clear--some conditional reasoning can be quite challenging--thanks!

~Steve
 Emily Haney-Caron
PowerScore Staff
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#33329
Hi LSATer,

A is a mistaken reversal of D; it flips the sufficient and necessary conditions, without negating them. To help you figure out what this does in practice, can you try writing out what you think A and D are saying? Basically, expound on each one, using more words to say what you think it means. That might make it so it is clear to you why D is better than A (because they'll have completely different meanings, and only one will make sense in the context of the argument). If so, great! If not, it will help us figure out where you're getting a bit off track, and will help us patch any holes in your understanding.

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