Light is registered in the retina when photons hit molecules of the pigment rhodopsin and change the molecules’ shape. Even when they have not been struck by photons of light, rhodopsin molecules sometimes change shape because of normal molecular motion, thereby introducing error into the visual system. The amount of this molecular motion is directly proportional to the temperature of the retina.

Summary
In the retina, light is registered when photons make contact with molecules of rhodopsin and cause the molecules to change shape. Rhodopsin molecules sometimes change shape caused by normal molecular motion, which causes errors in the visual system. The amount of normal molecular motion is directly proportional to the temperature of the retina.

Strongly Supported Conclusions
The warmer the retina, the higher the chance that errors in the visual system occur.

A
The temperature of an animal’s retina depends on the amount of light the retina is absorbing.
This answer is not supported. We don’t know whether the amount of light the retina absorbs actually causes the retina to change in temperature.
B
The visual systems of animals whose body temperature matches that of their surroundings are more error-prone in hot surroundings than in cold ones.
This answer is strongly supported. If the amount of normal molecular motion that causes visual errors is proportional to the temperature of the retina, then the warmer an animals’ environment the more error-prone that animal’s visual system is.
C
As the temperature of the retina rises, rhodopsin molecules react more slowly to being struck by photons.
This answer is unsupported. We don’t know from the stimulus how quickly rhodopsin reacts after being struck by photons.
D
Rhodopsin molecules are more sensitive to photons in animals whose retinas have large surface areas than in animals whose retinas have small surface areas.
This answer is unsupported. We don’t know from the stimulus if the surface area of an animal’s retina is correlated with the sensitivity of rhodopsin molecules.
E
Molecules of rhodopsin are the only pigment molecules that occur naturally in the retina.
This answer is unsupported. We don’t know whether rhodopsin is the only pigment molecule. We only know that it is an example of a naturally occurring pigment molecule.

22 comments

Critic: Political utility determines the popularity of a metaphor. In authoritarian societies, the metaphor of society as a human body governed by a head is pervasive. Therefore, the society-as-body metaphor, with its connection between society’s proper functioning and governance by a head, promotes greater acceptance of authoritarian repression than do other metaphors, such as likening society to a family.

Summarize Argument
The critic concludes the “society-as-body” metaphor justifies authoritarian rule better than other metaphors. Why? Because metaphors are popular to the extent they’re politically useful, and the society-as-body metaphor is popular in authoritarian societies.

Notable Assumptions
The critic assumes there’s no political use for the society-as-body metaphor except to justify authoritarian repression. He also assumes the society-as-family metaphor and the other metaphors mentioned are less popular in authoritarian societies than the society-as-body metaphor.

A
In authoritarian societies, the metaphor of society as a family is just as pervasive as the society-as-body metaphor.
This disputes the author’s assumption that the society-as-family metaphor is less popular than the society-as-body metaphor. If both metaphors are equally widespread, then the society-as-body metaphor cannot be popular simply because it justifies authoritarian rule.
B
Every society tries to justify the legitimacy of its government through the use of metaphor.
This strengthens the critic’s argument. It explains why the society-as-body metaphor would be politically useful to authoritarian governments.
C
The metaphor of society as a human body is sometimes used in nonauthoritarian societies.
This doesn’t say the society-as-body metaphor is popular in nonauthoritarian societies. It may be quite rare, in which case its relative popularity in authoritarian societies still supports the argument.
D
Authoritarian leaders are always searching for new metaphors for society in their effort to maintain their power.
This doesn’t say the society-as-body metaphor becomes less useful to authoritarian leaders over time—they can search for new metaphors without abandoning old ones.
E
The metaphor of society as a human body governed by a head is rarely used in liberal democracies.
This strengthens the argument. It supports the critic’s claim that metaphors are popular to the extent they’re politically useful, since it suggests the society-as-body metaphor is much more popular in authoritarian societies than in liberal democracies.

8 comments

Though many insects die soon after reproducing for the first time, some may live for years after the survival of the next generation has been secured. Among the latter are some insects that work for the benefit of the ecosystem—for example, bees.

Summary
Many insects die soon after reproducing the first time.
Some insects live for years after reproducing the first time. Some of these insects that live for a longer time help the ecosystem. Bees are one example of these beneficial insects.

Very Strongly Supported Conclusions
At least some bees do not die soon after reproducing for the first time.

A
Survival of the species, rather than of the individual, is the goal of most insect populations.
We don’t know what insect populations find to be the most important goal. We might have enough to say they want to reproduce. But we don’t know that this is the most important goal for insects.
B
Insects that do not play a vital role in the ecosystem are more likely to die after reproducing for the first time.
We don’t know about comparative likelihood of death after reproduction. We know some bees die soon after, and some don’t. We don’t know what kind of insect is more likely to be a kind that dies soon after vs. later.
C
Most bees live well beyond the onset of the generation that follows them.
We know that bees live for “years after the next generation has been secured.” But we don’t know whether this is “well beyond the onset of the generation that follows.” Maybe bees die very soon into the next geneneration’s life. This can still be “years after the next generation has been secured.”
D
Those bees that reproduce do not always die soon after reproducing for the first time.
Strongly supported, because we know bees are among the insects that live for years after reproducing for the first time. So some bees do not die soon after reproducing for the first time.
E
Most insects are hatched self-sufficient and do not need to be cared for by adult insects.
We don’t know what proportion of insects are self-sufficient after hatching.

4 comments

Lea: Contemporary art has become big business. Nowadays art has less to do with self-expression than with making money. The work of contemporary artists is utterly bereft of spontaneity and creativity, as a visit to any art gallery demonstrates.

Susan: I disagree. One can still find spontaneous, innovative new artwork in most of the smaller, independent galleries.

Speaker 1 Summary

Lea tells us that art today is more about making money and less about self-expression. She also asserts that the work of artists today doesn’t have any spontaneity or creativity, and that we can see this by going to any art gallery.

Speaker 2 Summary

Susan states that we can still find spontaneous, innovative art today in smaller, independent art galleries.

Objective

We’re looking for a point of disagreement. They disagree about whether there exists artwork today that is spontaneous and creative/innovative. Lea thinks there isn’t. Susan thinks there is.

A
large galleries contain creative artwork

Susan has no opinion. We know she thinks we can find innovative work in most of the smaller, independent galleries. But we don’t know what she thinks about large galleries.

B
most galleries contain some artwork that lacks spontaneity and creativity

Susan has no opinion. We know her opinion about smaller, independent galleries. But we don’t know whether these galleries make up over half of all galleries. So we don’t know what Susan thinks about most galleries.

C
contemporary art has become big business

Susan has no opinion. We don’t know what she thinks about whether art is more about making money or self expression.

D
some smaller art galleries still exhibit creative new artwork

This is a point of disagreement. Lea thinks there isn’t any spontaneous, creative contemporary artwork in any gallery today. Susan thinks we can find this kind of work in most of the smaller, independent galleries.

E
contemporary art, in general, is much less concerned with self-expression than older art is

Susan has no opinion. We don’t know whether she thinks art today is more based on making money or on self expression.


9 comments

Philosopher: People are not intellectually well suited to live in large, bureaucratic societies. Therefore, people can find happiness, if at all, only in smaller political units such as villages.

Summarize Argument

The philosopher concludes that, if people can find happiness at all, they can only do so in smaller communities, like villages. She supports this by saying that people aren’t intellectually well suited to live in large, bureaucratic societies.

Identify and Describe Flaw

The philosopher’s reasoning is flawed because she makes a key assumption. By concluding that people can only find happiness in small communities because they aren’t intellectually well suited to large ones, the philosopher must assume that people cannot find happiness in a society that they aren’t intellectually well suited to.

She ignores the fact that some people might be able to find happiness in large bureaucratic societies, even though they’re not intellectually well suited to them.

A
no one can ever be happy living in a society in which she or he is not intellectually well suited to live

In order to draw her conclusion, the philosopher takes for granted that people cannot be happy in a society that they aren’t intellectually well suited to. But what if some people can be happy in large, bureaucratic societies, even though they’re not well suited to live there?

B
the primary purpose of small political units such as villages is to make people happy

The author never makes this claim, nor does she take it for granted. She says that “people can find happiness, if at all, only in smaller political units.” She never claims that these communities’ purpose is to make people happy, or even that they will make people happy at all.

C
all societies that are plagued by excessive bureaucracy are large

The author never makes this claim, nor does she take it for granted. She just says that people aren’t well suited to live in large, bureaucratic societies. Maybe small bureaucratic societies exist, or maybe they don’t; it doesn’t affect the argument either way.

D
anyone who lives in a village or other small political unit that is not excessively bureaucratic can find happiness

The author doesn't make this assumption. She says that “people can find happiness, if at all, only in smaller political units.” She never assumes that people in small political units actually can or will find happiness.

E
everyone is willing to live in villages or other small political units

The author doesn’t make this assumption. Her argument isn’t addressing where people may or may not be willing to live. It’s just addressing where people must live in order to potentially find happiness.


2 comments