#8 - Lobsters and other crustaceans eaten by humans are more

[Adam Tyson]

Remember that the conclusion we want to weaken here, aheartofsunshine, is that the proposal to reroute the sewage offshore is pointless. To weaken that, we want to show that the proposal does, in fact, have a point. Answer C fails to give the proposal a point, because it doesn't give us a reason to get rid of the sewage. In fact, one could say that it strengthens the argument rather than weakening it, because it shows us that the sewage isn't doing anything to harm the breeding habits of the lobsters. At least in that one regard, the sewage just doesn't matter, so why bother to reroute it? Doing so would be pointless!

Don't add facts or speculation to an answer choice - it needs to stand or fall all on its own. We shouldn't not be going beyond that answer to make assumptions about whether it's good or bad that lobsters are breeding just as readily. Take it at face value - it's just saying that the sewage doesn't appear to have a particular effect. When we "help" answers by adding our own assumptions and outside information, we are heading down a dangerous path, where wrong answer lie in wait to tear down our scores!

[carlysnoble]

I am confused why the answer is not (B), lobsters, like other crustaceans, live longer in the open ocean than in industrial harbors.

I am still unsure of how much can be assumed, but I thought it was reasonable to assume, especially because the question tells us that sewage causes at least one disease, that Lobsters live shorter in industrial harbors because of sewage. Thus, moving sewage to open ocean and reducing the amount of sewage in the harbor may increase the life span of lobsters, to the point where they do live long enough to be harmed by diseases. That would weaken the argument and demonstrate why the proposal would not be pointless. Like a “the premise that lobsters don’t live long enough is true, but consider why the premise is that way” answer.

[carlysnoble]

I am confused why the answer is not (B), lobsters, like other crustaceans, live longer in the open ocean than in industrial harbors.

I am still unsure of how much can be assumed, but I thought it was reasonable to assume, especially because the question tells us that sewage causes at least one disease, that Lobsters live shorter in industrial harbors because of sewage. Thus, moving sewage to open ocean and reducing the amount of sewage in the harbor may increase the life span of lobsters, to the point where they do live long enough to be harmed by diseases. That would weaken the argument and demonstrate why the proposal would not be pointless. Like a “the premise that lobsters don’t live long enough is true, but consider why the premise is that way” answer.

To add on, I am also not sure why the urge is to pick a conclusion that ties to gill disease, aka find an argument that demonstrates how humans may still contract gill disease, because that is not the argument. The argument is that the proposal is pointless. It doesn’t say in the stimulus that the proposal is to fix the amount of gill disease, so why must the answer tie back to that?

Why can we make assumptions like the proposal was designed to protect humans from having lobsters that contract gil disease but not that knowing A) sewage causes disease and B) hardly any animal lives long enough to be harmed by this disease, the sewage may be creating another disease that is shortening their life?

[Rachael Wilkenfeld]

Hi Carly,

We don't pick the conclusion--the author of the stimulus does. Here, the conclusion is that the proposal to move the sewage offshore is pointless. Why? Because even though the sewage can cause gill disease in lobsters, they don't live long enough in the harbor to be harmed by the disease.

We are looking for what is necessary for the conclusion. For the conclusion "the proposal is pointless" to work, there can't be any point to the proposal. An assumption that eliminates a possible reason the proposal would help would be required.

Let's use the assumption negation technique on answer choice (B). If we negate that answer choice, we would have that lobsters do not live longer in the open water. Does that harm our argument? Not really. It doesn't matter how long lobsters live in the open ocean because we only really care about harbor lobsters. The proposal to reroute the sewage is about the harbor lobsters not the ocean lobsters.

We can't really assume that harbor lobsters are dying due to the disease. It could easily be because of easier fishing, or boats running into them.

We have to assume that the gill disease doesn't harm humans though. Because if it does harm humans, then the proposal wouldn't be pointless. It would be to protect the humans. Therefore, if we can conclude that the proposal is pointless, it assumes that the gill disease not only doesn't harm lobsters, but also doesn't harm humans either.

Hope that helps!

[hinarizvi]

For answer choice A, is it unreasonable to assume that rerouting the sewage water could also get rid of other contaminants? I picked A because I was thinking if there are other contaminants in the sewage water, then maybe rerouting that water ISN'T pointless because it could still get rid of other contaminants? Can you also elaborate on what answer choice C is saying? Is it saying the lobsters can breed as easily in sewage water as they can in unpolluted water? I made an assumption with this one that if they breed as easily, maybe the reproduce and they die before they can get gill disease but their offspring could get it? Can you help me understand why these assumptions aren't reasonable? Thanks!

[Dave Killoran]

For answer choice A, is it unreasonable to assume that rerouting the sewage water could also get rid of other contaminants?

I'd say it is unreasonable, in part because the argument and the answer makes it clear that there's sewage but that there are also other contaminants in the harbor. So removing the sewage is one thing, but I don't see how that automatically eliminates the other stuff, and LSAC would say that's an unwarranted assumption to think it removes it as well.

Can you also elaborate on what answer choice C is saying? Is it saying the lobsters can breed as easily in sewage water as they can in unpolluted water? I made an assumption with this one that if they breed as easily, maybe the reproduce and they die before they can get gill disease but their offspring could get it? Can you help me understand why these assumptions aren't reasonable? Thanks!

Yes, it's indicating that lobster breeding won't be affected by the kind of water they are in. As for your assumption there, LSAC would say you've leapt too far out ahead of what we know. Just because they breed as readily doesn't tell us anything about what they pass along to their offspring (maybe lobsters do not pass along their diseases to their offspring).


Thanks!