#7 - Naturalist: Different nonhuman primate species exhibit

[lkr123]

Could someone please explain why C is a better answer than e? Thank you!

[Luke Haqq]

Hi lkr123!

Answer (E) states, "Not all nonhuman primates understands tool use." This is a must be true question, so we need something that has to be the case based on the information given. The information talks only about chimpanzees and orangutang; the first plays with a screwdriver before moving on to something else, and the second uses it to open its cage. So it might seem likely that chimpanzees don't understand tool use--but we don't know this to be the case. It might be the case that when a different tool is set in front of a chimpanzee, it then uses it as we would. We don't know what would happen in that possibility.

Answer (C), by contrast ("some nonhuman primates are capable of deception"), has to be true based on the information given. Namely, we're told that "...an orangutan is likely to pretend to ignore the tool at first..." and then dismantle its own cage when the zookeeper isn't looking. The naturalist making the statements looked at how two different primates acted in particular scenarios, and by noticing the orangutan's behavior then made a conclusion about what it was likely to do. So we know that it must be true, according to the naturalist's statements, that some nonhuman primates are capable of deception (namely, because she saw orangutan doing so by pretending not to notice the tool).

[T.B.Justin]

Hey PS,

Thanks for your explanation Luke.

I had a different thought about answer choice E:

And read it as "Some nonhuman primates understand tool use," and since the naturalist uses weak language with the orangutan "may" use the screwdriver to "try" to dismantle its cage, I feel that shows that the animal has an idea of what that tool is used for but not enough to say they understand how to properly use that tool.

[menkenj]

What got me here was the "likely to pretend" phrasing. Just because they are likely to doesn't mean they will pretend. Do we know for certain that some nonhuman primates are capable of deception? If deception is likely does that mean they are capable? Seems like the difference between C and E is the choosing the least worst answer choice.

[Adam Tyson]

If an orangutan is likely to pretend, menkenj, that means they will pretend more often than not, and even if only one orangutan pretends just one time, that is enough to show that at least one primate is capable of deception. Pretending is a form of deception. And you cannot be likely to do something unless you are capable of doing it!

It seems we never addressed an old question in this thread from T.B.Justin that should be addressed: "not all" does not mean some! This is because the concept of "not all" includes the concept of "none." If I say "not all of my children are doctors," it could be the case that none of my children are doctors. Saying "not all" in the real world usually implies some, but in logical terms (which is how we must interpret statements on the LSAT), it only means "less than all." Since "none" is less than all, "not all" includes "none." So answer E does not imply that some primates do understand tool use.

[marilati]

To clarify, this stimulus leaves open the possibility that all non-human primates understand how to use tools?

[Bob O'Halloran]

Hi Marilati,
That is correct!
Also note that the stimulus gives us no direct evidence that the chimpanzees didn't understand tool use, but does gives us direct evidence that orangutans are capable of deception.
Let us know if you have any other question.
Bob

[SGD2021]

Hello,

For must be true questions like this, would any kind of answer choice that tries to state what the individual knows or thinks automatically be incorrect since we can't know for sure what they know/think (as long as the stimulus isnt talking specifically about what the individual's thoughts are) ?

[Rachael Wilkenfeld]

Hi SGD,

I'm not sure what individuals you are referring to here. Do you mean the speaker/naturalist? We can't read the speaker's mind, but we can draw conclusions based on the direct statements made by the naturalist. I'm not entirely sure what your question is without seeing an example of your scenario.