Q7 - Although instinct enables organisms

[jrany12]

Could somebody please explain why the answer to this question is B and not E?
The stimulus states that "no insect brain has yet reached a size capable of providing a sufficiently large number of neurons" (to make complex responses to stimuli). So wouldn't it make sense that brains of insect size or smaller engage in purely instinctual behavior (incapable of making complex responses to stimuli)?

[ManhattanPrepLSAT2]

The fact that non-instinctual behavior requires a larger brain does not mean every larger brain must be capable of non-instinctual behavior. (Just because buying a fancy car requires a lot of $ doesn't mean everyone with a lot of money drives an expensive car.) Some of these larger brains can still, for all we know, rely on purely instinctual behavior. Therefore, we can't say that "only" those with small brains behave this way.

(B) is much more sound. We know insects don't have the physical brain size required for non-instinctual behavior, so it must be true they can't engage in it.

[jrany12]

"no insect brain has yet reached a size capable of providing a sufficiently large number of neurons"
I took this "capable size" as a threshold size, in which all sizes larger than this either can or not engage in instinctual behavior, but any size below this threshold "capable size" could not. Since there is a threshold size, any size below it is incapable of providing a sufficient number of neurons. Am I over thinking this?
Would it be more accurate to read this statement from the stimulus as "no insect brain has yet reached a size capable of providing a sufficiently large number of neurons" (for insects)? Meaning, conclusions cannot be drawn concerning other organisms, whether they have larger or smaller brains?

[chike_eze]

Missed this question because (B) seemed too strong. But I didn't notice the conditional that makes (B) a completely valid inference.

"Brain capable of flexible (non-instinctual) behavior must have a large number of neurons..."
> Not instinctual --> Sufficiently large # neurons
> Not Sufficiently large # neurons --> Instinctual (contra)

"No insect...reached size of sufficiently large number of neurons..."
> Insects --> Not Sufficiently large # neurons

therefore,
Insects --> Instinctual (valid inference)

(B) "Insect exclusively instinctual". Insects --> Instinctual

(A) "elaborate brain mechanisms". Term shift.
(C) "larger brains". Other insects could have larger brains but insufficiently large # neurons.
(D) "large brains". Large brain does not necessarily mean sufficiently large # of neurons.
(E) "Only organisms with less than or equal to insect brain size". Some organism could have a larger brain than the largest insect brain and still not meet the threshold number of neurons required.

[giladedelman]

Yes, good explanation. Put very simply, having a big brain is necessary, but not sufficient, for engaging in non-instinctual behavior.

[gilad.bendheim]

But why do we have to take for granted that the only two possible behaviors are flexible and instinctual? Perhaps there is a third category that all organisms are capable of, which, if insects had, would make (B) incorrect.

[chike_eze]

But why do we have to take for granted that the only two possible behaviors are flexible and instinctual? Perhaps there is a third category that all organisms are capable of, which, if insects had, would make (B) incorrect.

Because this is an in inference question, more specifically, it is a MUST BE TRUE question with a conditional relationship.

Therefore, we can infer based on the sufficient -> necessary conditions in the stimulus.

My Assumption: "Can be properly inferred" = "MUST BE TRUE"

[gilad.bendheim]

Thanks. I guess my question is whether (B) can be properly inferred. Based on the stimulas we can infer that
Insects --> ~Large enough brain
and therefore
Insects --> ~ Flexible thinkers.
Answer (B) seems, at least to me, to require another assumption, namely that there is no way to think other than either flexibly or instinctually, so that ~flexible thinker --> EXCLUSIVELY instinctual.

Maybe I'm missing something...

[chunsun..b]

The paragraph says: "... noninstinctual (also called flexible) behavior."
So basically, a behavior is either instinctual or flexible, but nothing else, because flexible behavior is noninstinctual behavior by definition.

[andreperez7]

So the prefix "non-" implies a binary relationship?

So, to parallel the stimulus, if I say person A is not a non-knife wielding maniac, then that means she is a knife wielding maniac, correct?

[ohthatpatrick]

You're taking it a little too far there.

If you say
"person A is not a non-knife wielding maniac"

You cannot infer that
"she is a knife wielding maniac"

Who said she's a maniac at all?

Your example was too complex because you were negating something that had a noun and an adjective.

If I say, "Bob is not [adjective+noun]"
then either Bob is not that adjective, not that noun, or both.

The example here was much simpler.

Binaries always add up to 100%.

Everything is either
instinctual or non-instinctual.

Since the passage gave us permission to equate
"flexible" with "non-instinctual", then we can say

Everything is either
instinctual or flexible

We can't say that everyone is either
a knife-wielding maniac or a non-knife wielding maniac

Because why does everyone have to be a maniac?

[andreperez7]

Very good point! Thanks for breaking that down in such detail -- I see things much more clearly. The more complex scenario of adjective and noun does bring in more possibilities than the original. I could see the LSAT using something along the lines of my answer as a trap answer for an infer question.

But let me amend that and try once more: Can I say, then, that if you are not apathetic (defined as not caring) then you care?

[ohthatpatrick]

Fo' sho.