## PT 68, Section 3, Question 20

Prepare for the LSAT or discuss it with others in this forum.
beyondabilities

Posts: 27
Joined: Wed Aug 29, 2012 4:10 am

### PT 68, Section 3, Question 20

Its the question about scientists and galaxy exploration.

Whats the difference between A and D?

Manhattan LSAT Noah

Posts: 744
Joined: Tue Oct 12, 2010 8:43 am

### Re: PT 68, Section 3, Question 20

beyondabilities wrote:Its the question about scientists and galaxy exploration.

Whats the difference between A and D?

Tough question. Someone (I'm guessing you!) also posted this on our forums, so I'll answer it in both places:

The argument begins by laying out a prediction, which we can smell will get debunked. In the second sentence, we learn of a consequence that would flow from that prediction proving true. This consequence is both that most people would be alive and that we'd likely be alive then too. Then the argument delivers the kill by pointing out the consequences have not occurred, so the prediction must be wrong.

Remember that we're not asked to identify the flaw in this argument - we're just assembling an outline of moves the argument makes.

(A) is tempting since it references something not occurring and thus a low probability. However, there's nothing here about a prediction nor about consequences not panning out. If we force the argument into (A), it'd be something like: since we haven't gone into space, we probably never will. That seems close, but it's missing the whole bit about setting up the consequence.

(B) is fancy but wrong. The conclusion--that the prediction won't happen--doesn't contradict any premise. Don't confuse debunking a theory with contradicting a premise. Plus, this sort of answer is always fishy--LSAT arguments, unless they're flawed--don't conclude against a premise. (Cue zombie voice: accept premises, doubt whether they definitively support the conclusion.)

(C) is silly and contradicted. The argument actually does assume that present facts tell us something about predictions.

(D) has it. The event that is likely on a given hypothesis is us being alive during the colonization period. The fact that this has not occurred--I'm not seeing any Starships out my window--means we probably won't ever colonize the stars. Sad.

(E) misses by a mile. Where's the prediction bashing? Who forgot the consequences?

beyondabilities

Posts: 27
Joined: Wed Aug 29, 2012 4:10 am

### Re: PT 68, Section 3, Question 20

I think this just clicked.

So the scientist is using the occurrence of an event that would likely be caused by the prediction as a gauge of whether or not the prediction is true or false (D) INSTEAD of using the fulfillment of the prediction as a gauge (A).

Its like if we have a conditional that states A --> B and want to prove that A didn't happen; we can say because we don't see A, A didn't happen or we can saw because a consequence of A i.e. B did not happen happen, its probably true that A didn't happen.

The stimulus is committing a temporal fallacy, correct?

Manhattan LSAT Noah

Posts: 744
Joined: Tue Oct 12, 2010 8:43 am

### Re: PT 68, Section 3, Question 20

beyondabilities wrote:I think this just clicked.

So the scientist is using the occurrence of an event that would likely be caused by the prediction as a gauge of whether or not the prediction is true or false (D) INSTEAD of using the fulfillment of the prediction as a gauge (A).

Its like if we have a conditional that states A --> B and want to prove that A didn't happen; we can say because we don't see A, A didn't happen or we can saw because a consequence of A i.e. B did not happen happen, its probably true that A didn't happen.

The stimulus is committing a temporal fallacy, correct?

Looks like you're getting it.

T: travel --> M: majority --> W: we'd be there (probably)
we're not seeing W, so T is not true.

Yes, the argument sucks. To me, the "there's no reason to think we are unrepresentative --> odds are overwhelming we'd be alive" is the most glaring problem with this argument, but since I'm not asked to find the flaw, it's not important here.

beyondabilities

Posts: 27
Joined: Wed Aug 29, 2012 4:10 am

Thanks for this!