pt 69, s.1 Q 14 , investigators have not.. Forum

flash21 · Post by **flash21** » Tue Nov 10, 2015 9:05 pm

I got this question right, but I do not see a flaw? I read manhattan and I don't get it. This argument seems fine to me, but apparently it is flawed.

Can someone break it down for me please?

mohdban · Post by **mohdban** » Wed Nov 25, 2015 2:28 am

The investigators cannot prove that lightning caused the fire. The investigators cannot prove that campers started the fire. The trick is what the words "cannot prove" mean and what it means if we combine the two facts together. I will give the following example as an illustration:

I can only show that it is 30% likely that Phill killed John. I can also show that it is 30% likely that Kim killed John. Does it follow from this that it is is 30% likely that Phill or Kim killed John? No. The correct combined statement would be: I can show that is is 60% likely that either Phill or Kim killed John.

I hope this helps.

somethingElse · Post by **somethingElse** » Wed Nov 25, 2015 10:25 am

Post removed...

flash21 · Post by **flash21** » Wed Nov 25, 2015 1:34 pm

GUYS I'm sorry my brain cannot comprehend. The percentage thing is confusing me and something I don't really see the flaw still from your example.

I'm not sure why this is so hard of a flaw for me to understand though

somethingElse · Post by **somethingElse** » Wed Nov 25, 2015 5:42 pm

Post removed...

flash21 · Post by **flash21** » Wed Nov 25, 2015 6:46 pm

Am I just not understanding the final sentence of the stimulus's meaning? Is it saying that, therefore, neither of these things caused the blaze? IF thats the case, omfg dude that is the dumbest wording ever.

somethingElse · Post by **somethingElse** » Wed Nov 25, 2015 6:49 pm

Post removed...

flash21 · Post by **flash21** » Wed Nov 25, 2015 6:51 pm

somethingelse55 wrote:It's not saying quite that. It is saying that they haven't proven that the cause was one or the other. I.e. that they've narrowed it down to those two options.

OHH. I get it now. that is so subtle though. for me anyway.. did this just pop out at you? I don't think I'd ever get a Q like this right again jesus.

flash21 · Post by **flash21** » Wed Nov 25, 2015 6:54 pm

they have not proven that john stole the egg, and they have not proven that ed stole the egg.

therefore, they have not proven that ed or john stole the egg.

BUT WAIT.

They may just be deciding between these two theives, so not being able to decide between two options doesn't mean not proving who stole the egg at all!

IM SO SMART

somethingElse · Post by **somethingElse** » Wed Nov 25, 2015 6:55 pm

Post removed...

flash21 · Post by **flash21** » Wed Nov 25, 2015 7:09 pm

somethingelse55 wrote:For me personally it jumped out at me immediately once I saw answer choice A. But before that I wasn't quite sure.

And yep, you got it!

really strange, it just seemed like a valid argument, but luckily the argument structure was really easy to see so I got it right still. thanks