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Current time:0:00Total duration:8:13

Video transcript

let's see we're told a book tour will be successful if it is well publicized and the author is an established writer Julia is an established writer and her book tour was successful so her book tour must have been well publicized well just think about what they're saying they're saying a book tour will be successful so successful successful tour and it's going to that's going to happen if it is both well publicized well publicized publicized and the authors established writer plus established writer so the way it's set up they're saying if both of these things happen then you will have a successful tour but then they go on to say Julia is an established writer and they say her book tour was successful so therefore her book tour must have been well publicized well that doesn't necessarily fall out of the original statement the original statements don't say this is the only way that you're going to have a successful tour if this was the only way to have a successful tour then maybe this last statement might be reasonable but they don't say this isn't this is the only way to say this is a way of having a successful tour by have being well publicized and by being an established writer so let's read the question which of the following exhibits a pattern of flawed reasoning most closely parallel to the pattern of flawed reasoning exhibited by the argument above so statement a says this recipe will turn out only if one follows it exactly and uses high-quality ingredients so the recipe works so I'll call it they say turn out the recipe turns out only if follows exactly follows exact and and high-quality ingredients high quality high quality ingredients so if you do both of these things that's going to turn out author followed the recipe exactly so he followed it exactly and it turned out and it turned out thus author must Arthur must have used high quality ingredients so this one looks similar to what we did there where they're saying okay it turned out and it and he followed exactly and so he must have used high quality ingredients but the difference here if they're saying this recipe will turn out if and only if will turn out will turn out only or I should say they don't this one says this recipe will turn out only if so saying this is the only way to get it to turn out so if it turns out then both of these two things must be true and so it's reasonable to say that Arthur must have used high quality ingredients over here they didn't say a book tour will be will be successful only if if that was true then the argument would not have been flawed so I'll rule this one out even though it looks similar the difference here is they're saying only if this is the only way to get the recipe to turn out well over here they're not saying this is the only way to have a successful book tour choice B if a computer has the fastest microprocessor and the most memory available it will meet Alito's needs this year so if it's fast plus memory plus most memory plus most memory so if you have both of those it will meet Alito's needs it will meet Aleta's needs this computer met Alito's needs last year so it met Alito's needs last year so it must have had the fastest microprocessor and the most memory available so this one is different than our original statement because in the original statement we said ok we got a successful tour and she's an established writer and then they picked out one of the other conditions or one of the other ways to get a successful tour here they're saying hey the conclusion or we were able to meet the needs and then they're saying therefore both of the inputs must have happened so this is a little bit different so I would rule this out if cacti let me scroll all the way if cacti are kept in the shade and watered more than twice weekly they will die so shade plus 2 times watering watering they will die this cactus was kept in the shade it was kept in the shade and is now dead therefore it must have been watered more than twice weekly so this is this one looks really interesting because just looking at the argument doesn't necessarily mean that it must have been watered twice more than twice weekly it doesn't say that cactus will die only if they are kept in the shade and they are watered more than twice weekly if it was only if like we saw in choice a well then you might be able to make that conclusion but this is very similar to the original statement where the saying hey look if this and this happens then this is going to happen and then they give a situation would say okay it did die and one of the things happened and so they're trying to make the conclusion that the other input that other conditions must have happened but that's not necessarily the case it would only be the case if they said if cactus or the only way to kill the cactus is if they are kept in the shade and watered more than twice so this one looks like seems to have the exact same structure as our original argument I had the same flaw I should say so let's just verify the last two choices a house will suffer from dry rot and poor drainage only if it is built in your high water table so built high water table so if it is built near a high water table it will suffer dry rot dry rot plus poor drainage poor drainage this house suffers from dry rot and has poor drainage thus it must have been built near a high water table well the way this is different is actually this is only if it is built near a high water table so this one is actually a reasonable statement sake because they say only if it is built near a high water table this will happen so this is happening it's actually reasonable to say that it was built near a high water table so not only does this not as flawed or not flawed like our original statement but also is a different structure it's not saying hey there's two things that need to be true or there's two things if they were true would make our the last statement true so it has a different structure so I'd ruled this one out and this last choice if one wears a suit that has double vent and narrow lapels so double vents plus narrow lapels larra narrow lapels one will be fashionably dressed so then you will be fashionable I wish we were that easy the suit that Joseph wore to dinner last night had double vents and narrow narrow lapels so Joseph must have been fashionably dressed so this one if you assume this original part if you say hey if one wears a suit that has double events and narrow lapels one will be fashionably dressed if you accept that conditional that if you said this is true then actually the conclusion is fairly reasonable because Joseph is meeting those first two conditions and so if you believe them then you could say that he is he must have been fashionably dressed so this is a 1 it's not flawed the way the original argument was and it also fundamentally has a different structure so I feel good about choice see