#20- Sociologist: Climate and geology determine where human

[Roadto170]

Is it fair to say that answer choice C is the contrapositive of a premise in the stimulus. Although I missed this during my initial attempt, I am seeing this as a possibility now.

Premise: drastic shifts in climate always result in migrations ( Climate Shift (CS) > Migration (M))
C: A population remains settled only when the climate is fairly stable (Settled pop (-M) > Climate Fairly Stable (-CS).

Additionally, if this is the case, how should I pick this up during the test if I am not allowed/advised to use scratch paper?

Thanks!

[tessajw]

In terms of the LSAT, we were taught that in questions where Cause and Effect occurs, the author states that their is only one cause. We were taught that we should take the authors meaning to imply that there is only one cause for one effect. How come this rule doesnt apply to this question? Why is A not right, if the author, as described by powerscore, indicates that the cause always brings about the effect, therefor is the only cause.

[tessajw]

This is a direct response I have received from a power score staff regarding cause and effect:

"Hey Tessajw,

For cause and effect conditional logic, the stated cause must be the only cause of the effect. In this case, if the argument says reading causes a person to be intelligent, we must assume that no other factors cause a person to be intelligent. This is how the LSAT treats cause and effect arguments, which I understand is different from how we might use them in regular daily life. Because only 1 cause can bring about the 1 effect, we must assume that any other possible causes do not actually bring about intelligence - that is why these examples are used as defender assumptions. They help defend our argument against possible ways to weaken it.

I would suggest reviewing the lessons on cause and effect arguments in order to better understand this concept if it's still giving you trouble! Hope that helps."

So I am just confused.

[Luke Haqq]

Hi tessajw!

There seems to be a slight difference in the wording that takes answer choice (A) out of contention for a must be true question. Note that the stimulus only refers to "drastic shifts in climate" always resulting in migration. Thus, if answer choice (A) had said "drastic shifts in climate cause migration," then it would have been true based on the stimulus. However, (A) makes a slightly different claim in asserting that climate in general is the primary cause of migration, which we don't know to be true based off the stimulus.

[zebrowski]

CJ12345:,

Note the mixed language: "always" is a conditional indicator, and "result in" is a causal indicator. Not only will one thing result in another, it will always result in it. So we know that anytime the cause happens, the effect will happen. That is indeed a conditional relationship.

Robert Carroll

I am not sure about that.

This strikes me as equivocating between causal and conditional language. Surely, a relationship cannot be both causal and conditional. Causal relationships obtain between events, while conditional relationships obtain between symbols or strings of symbols.

Drastic shifts in climate are events that result in migrations--other events. The relationship between them is causal. What difference does the word "always" make?

And if the relationship between drastic shifts in climate and migrations is causal, how can you conclude "NOT migrations NOT drastic shifts in climate" by the law of contraposition?

Even if you could use the law of contraposition, you would run into another problem. Although "NOT migrations" is the same thing as a "settled population," I think it is a stretch to conclude that "NOT drastic shifts in climate" is the same thing as a "fairly stable climate." A climate that shifts all the time, albeit not drastically, is not "fairly stable."

Thanks!

[Jeff Wren]

Hi zebrowski,

While conditional and causal reasoning differ and should be thought of separately, there are times when a statement can contain both types of reasoning. In other words, the two concepts can in fact overlap.

You wrote,

Causal relationships obtain between events, while conditional relationships obtain between symbols or strings of symbols.

Unfortunately, that is not quite right. Conditional reasoning, as the name implies, involves a relationship between a sufficient and necessary condition. Those conditions can be, and very often are, events or circumstances. While it is true that conditional relationships can be shown/diagrammed symbolically, those symbols represent the events or circumstances mentioned in the original conditional statement.

Here's an example:

If it rains, then the grass will get wet.

This sentence is worded as a conditional statement and can be diagrammed as such. However, the sentence also contains implied causal reasoning, since the rain does in fact cause the grass to get wet, so it would be completely reasonable to think of this relationship in causal terms.

Here's another example:

Smoking always causes cancer.

This sentences clearly expresses causal reasoning; however, the inclusion of the word "always" indicates that smoking is also sufficient to guarantee cancer, so this is also conditional.

You asked:

What difference does the word "always" make?

It makes all the difference, as it indicates conditional reasoning. Because "drastic shifts in climate always result in migrations"(my emphasis), then a lack of migration would guarantee that there are no drastic shifts in climate via the contrapositive.

As a general rule, if a statement does contain both conditional and causal reasoning, focusing on (and diagramming) the conditional reasoning is often more helpful to solving the question.

You wrote,

I think it is a stretch to conclude that "NOT drastic shifts in climate" is the same thing as a "fairly stable climate."

This is one of those situations where you're probably being too nitpicky. While it's important to read very carefully and note when terms change, you also have to pick the best answer available and realize that the test makers do sometimes use terms that are roughly getting at the same idea without using the exact same words that appeared in the stimulus. Here, "fairly stable" should be interpreted as "not drastic shifts." The word "fairly" is really the key here. Some changes are fine, just not drastic ones. Drastic shifts would be the opposite of fairly stable.

More information on conditional and causal reasoning, including the differences between them, can be found in "The Logical Reasoning Bible."