#7 - Although instinct enables organisms to make complex

[Luke Haqq]

Hi Jessica!

To your questions,

How can we prove that insect behavior is EXCLUSIVELY instinctual? Don't we just know that it is NOT instinctual? What if there is another behavior that the animal possesses that is neither instinctual nor non-instinctual?

I would set up the conditional reasoning a bit differently than the diagram you posted--

• (1) noninstinctual/capable of flexible behavior large # neurons
  
  (2) insect brain ~(large # neurons)

From these, what we know is that insects are not noninstinctual. This can be seen by linking (1) with the contrapositive of (2) to get:

• noninstinctual/capable of flexible behavior large # neurons ~(insect brain), or just
  
  noninstinctual ~(insect brain); finally, the contrapositive of that is:
  
  insect brain ~(noninstinctual)

And another of way of saying that insect behavior is not noninstinctual is to say that it is instinctual. To the question of why it's exclusively instinctual, this stimulus seems to use instinctual/noninstinctual as logical opposites of one another. That is, it makes a claim that noninstinctual behavior is only possible if an organism has a large number of neurons--either an organism has the sufficient number of neurons, or it does not. As to a possible behavior that isn't instinctual/noninstinctual, it couldn't be the correct answer on this one, since it's a must-be-true question, and we don't know about such a behavior from the stimulus.

To the question of why (A) is incorrect, we don't have any information as to how certain organisms "usually" behave, so we can't know a statement about whether the behavior is usually instinctual or usually noninstinctual in organisms with elaborate brain mechanisms.

Hope that helps!

[tejinder12]

Why is this?
(1) noninstinctual/capable of flexible behavior large # neurons

and not this?

(1)instinctual behavior NOT large # neurons

I did this:
(1)instinctual behavior NOT large # neurons

because for the other condition it is

(1)instinctual NOT reasoning


Below I added a quote from someone who works for powerscore. The person said that the negative should not be in the sufficient. I know im wrong but im just trying to understand where i'm going wrong!

Many people place the negative in the sufficient, but this is incorrect. The diagram: not A -> O actually means that if you do not have an apple, you must have an orange. In other words, it would be representing the statement that everything that is not an apple is an orange, meaning that everything is either an apple or an orange. This is not what the original sentence means.

A lot of people confuse the "not both" rule with the "either/or" rule. There is a good discussion of these concepts on p. 2-48 to 2-50.

These concepts will also be discussed further in lesson 5 grouping games, when we introduce the double-not arrow.

I hope that this helps answer your question.

Best,
Jeff

[Adam Tyson]

The tricky thing here is in the language of "requires far fewer," tejinder12. This language does not mean that instinctual behavior is sufficient to prove that fewer nerve cells are available. Instead, it means that it does not require as many nerve cells as noninstinctual behavior does. In other words, a relatively large number of nerve cells are not necessary. That's not a conditional claim, but a non-conditional claim - it tells us that instinctual behavior is NOT sufficient to show a large number of those cells (because instinctual behavior doesn't need/require/make necessary that larger number). Beware of claims that tell us that one thing is NOT sufficient to show another thing.

The second sentence is where the conditional reasoning in this stimulus really kicks in. There, the author tells us that noninstinctual/flexible behavior requires (is sufficient for) a large number of neurons. If you exhibit flexible behavior, you must have a large number of neurons; insects do not meet that necessary condition, so their behavior cannot be flexible, and since there are only two options (instinctual and noninstinctual, aka flexible), insect behavior must be entirely instinctual.

Put another way, there is nothing in this stimulus to suggest that a creature with a large number of neurons is incapable of instinctual behavior, which your conditional diagram would require to be true. Insects can only be instinctual; humans may be able to do both.

This stimulus illustrates one of the many challenges posed by the vagueness inherent in much of the English language! It would change my analysis entirely, and would agree with yours, if the stimulus had instead said "instinctual behavior requires that the animal have far fewer neurons than an animal who exhibits noninstinctual behavior." That would make having fewer neurons a necessary condition. Here, though, the language means "doesn't require as many".

I hope that helps!

[lunsandy]

Hi there,

I am struggling to see how B) is the correct answer. I diagramed as FB --> L#N. We know that no insect brains have L#N. So /L#N ---> /FB. I thought from this all we can conclude is no insect brains are flexible behaviour. Because we do not have a sufficiently large number of neurons, how can we equate not sufficient large neurons to be fewer nerve cells (instinctual behaviour)?

Do I have to assume it is instinctual since the stim just gives us two options? I just feel like there is too large of a "jump."

[James Finch]

Hi Luna,

The stimulus here actually sets up a second conditional, based on information present in the first sentence:

If an organism exhibits complex responses to stimuli, then its behavior is either flexible, instinctual, or both. So:

CRS FB or IB

Combined with the contrapositive of the conditional that we're given in the third sentence (and which you noted):

L#N FB

We're left with

CRS FB IB

As you note, an assumption is still required to get to answer choice (B), as nothing in the stimulus explicitly states that insects exhibit complex responses to stimuli. Occasionally outside assumptions based upon what is considered widely held knowledge of the subject in question do crop up, but they are fortunately rare. Here the test makers assume familiarity with insects and their complex responses to stimuli. (B) is correct because, as a Must Be True question, this answer choice comes from proper understanding of the conditional reasoning in the stimulus, which isn't present in the other answer choices. So one could also get to the correct answer by process of elimination, even if there is an assumption/leap required.

Hope this helps!

[lunsandy]

Hi Powerscore,

I got the question right from diagraming during the actual exam, but I am going through the exam now and want to be sure I got rid of A for the correct reason.

Besides the fact of "usually" error as claimed by @Luke Haqq, can we say that "elaborate brain" does not equate to instinctual behaviours of organisms that make complex responses nor can we conclude that they are non-instinctual because we only know that non-instinctual organisms are capable of flexible behaviour and must have large number of neurons. Thus, we can't conclude whether these "elaborate brain" organisms are either instinctual or non-instinctual?

Thanks!

[James Finch]

Hi Lunsandy,

"Elaborate brain mechanisms" here is synonymous with "brain mechanism with large numbers of neurons," a necessary condition for flexible behavior. However, as it's not a biconditional, we can't reverse the arrows and conclude that the sufficient condition, flexible behavior, is true or not just because we know the necessary condition to be true. This error is know as a Mistaken Reversal, and commonly found in the Logical Reasoning sections. Our actual diagram is:

Flexible Behavior Large # Neurons

or

Large # Neurons Flexible Behavior

Answer choice (A) is saying Large # Neurons Flexible Behavior, a Mistaken Reversal. The "usually," a clear departure from the scope of the stimulus, is just another clue that (A) is an incorrect answer choice.

Hope this helps!

[anthonychernandez]

I hope this question hasn't been asked previously in the forum.

I chose the correct answer B, but spent lots of time during my timed practice test deliberating between B and E. What scared me about B was the word "exclusively". I eventually justified it because the way the stimulus is speaking about instinctual and noninstinctual (flexible) behavior, to me, implies that these are the only two types (or at least the only two to be concerned with in the stimulus).

Do we need to assume that instinctual and flexible are the ONLY two types of behavior? We should assume that there's not a third (or fourth, or fifth, or sixth) category of behavior out there?

Thanks,

Anthony

[Brook Miscoski]

Anthony,

A good reason for choosing (B) is that (E) is very weak. The stimulus is set up to show that insects operate on instinct, but there could be something above an insect that still operates on instinct. The stimulus didn't tell us that it was choosing the borderline animal.

I understand your trepidation about the word "exclusively." Remember that extreme words can be okay when the stimulus is absolute. The stimulus is presented as a dichotomy--instinctual versus flexible. The stimulus then tells you that insects don't have enough neurons to do flexible behavior, leaving the other side of the dichotomy--instinctual. So it's okay to pick (B).

Outside of tests, it would be a good idea to ask whether there is behavior that is not easily defined as either instinctual or flexible--whether there is something in between or indeterminate. However, on the test, the stimulus said that there's a quality and its logical opposite (instinctual and flexible), and you just have to allow that premise to exist even though, in reality, everyone with a reasonable amount of brains and experience knows that no one would be able to establish a clear and uncontested boundary between the two.

[na02]

If E had been "Organisms with brains of insect size or smaller only engage in purely instinctual behaviour" - would this have been correct? Or does it still not matter where the "only" goes, as we can't make any inferences about other organisms that are not insects..?

Thank you,
NY