WEBVTT 00:00:02.380 --> 00:00:06.604 We're right in the middle of reconstruction. We did stage one last 00:00:06.604 --> 00:00:11.485 week, cuz that's just close analysis. In the previous section we did stage two, 00:00:11.485 --> 00:00:16.746 which is to remove excess verbiage, and to put the explicit premises and conclusion 00:00:16.746 --> 00:00:21.690 into standard form. And this lecture is going to focus on stage three, which is 00:00:21.690 --> 00:00:27.078 the clarify the premises and to break them up. Where it's possible without distorting 00:00:27.078 --> 00:00:31.705 them. Let's start with step four, which is to clarify the premises and the 00:00:31.705 --> 00:00:37.375 conclusion, when it's needed. So we might need to clarify them just in order to make 00:00:37.375 --> 00:00:42.900 them easier to understand, or to make them less likely to mislead, and all that 00:00:42.900 --> 00:00:49.181 sounds pretty good. So let's try on this example. It was hot today, so it'll 00:00:49.181 --> 00:00:58.045 probably be hot tomorrow again. And we need to clarify that. What exactly counts 00:00:58.045 --> 00:01:04.742 as today? Is that, you know, the time when there's daylight, or does it also include 00:01:04.742 --> 00:01:10.482 night, even though night is not day? And what exactly do we mean by hot? How hot 00:01:10.482 --> 00:01:15.780 was it today, and how hot will it be tomorrow? And what, after all, is heat? 00:01:15.780 --> 00:01:20.444 And what about, it'll probably be hot tomorrow? Probability. That's a tough 00:01:20.444 --> 00:01:25.492 notion. We're going to spend a whole week on that later on in the course. And there 00:01:25.492 --> 00:01:30.284 are different kinds of probability, and I want to know what kind you're talking 00:01:30.284 --> 00:01:35.268 about here. And when you ask for example, about it will be hot tomorrow, what is, 00:01:35.268 --> 00:01:40.252 what does will mean? It means it's going to happen in the future, and what exactly 00:01:40.252 --> 00:01:45.364 is the future? And is the future real? Is time real? You can go a long way towards 00:01:45.364 --> 00:01:50.761 asking how to clarify that argument. But that's ridiculous, you know. We don't have 00:01:50.761 --> 00:01:56.498 to clarify a simple argument like it was hot today so it will probably be hot 00:01:56.498 --> 00:02:01.583 tomorrow. And it's lucky we don't have to clarify every word in the argument because 00:02:01.583 --> 00:02:05.948 we couldn't because after all when you explain one of the words or give a 00:02:05.948 --> 00:02:10.726 definition for it, it's going to be in terms of other words and then they have to 00:02:10.726 --> 00:02:15.209 get clarified and you'll never going to get to the end of it. The search for 00:02:15.209 --> 00:02:19.928 perfect clarity and absolute precision is impossible. You'll never complete that 00:02:19.928 --> 00:02:24.805 search. You'll never find perfect clarity or absolute precision, so give it up. What 00:02:24.805 --> 00:02:29.975 we should seek is not absolute precision, but adequate precision. Not absolute 00:02:29.975 --> 00:02:35.077 clarity, but adequate clarity. And that means that we ought to try to clear up 00:02:35.077 --> 00:02:40.448 those parts of the premises and conclusion that are likely to produce confusion 00:02:40.448 --> 00:02:45.819 later. And you have to be able to kind of predict whether this part of the argument 00:02:45.819 --> 00:02:50.961 needs to be clarified, because people are going to get confused by it. Now that's 00:02:50.961 --> 00:02:56.069 not going to be easy, and there's no simple or mechanical rule to tell you what 00:02:56.069 --> 00:03:00.725 needs to be clarified, and what doesn't need to be clarified. The only way to 00:03:00.725 --> 00:03:06.028 learn this skill is to go through some examples that will give you models of what 00:03:06.028 --> 00:03:11.717 needs to be clarified and what doesn't. Sometimes, you know, in clarity lies in a 00:03:11.717 --> 00:03:18.185 single word. In the 1980's Nancy Reagan used to say, just say no to drugs. What 00:03:18.185 --> 00:03:24.669 does that mean? Well, she is telling you not to use drugs, to say no when somebody 00:03:24.669 --> 00:03:31.235 offers you drugs or tries to tell you to use drugs. So, in effect, she's saying you 00:03:31.235 --> 00:03:38.688 ought not to use drugs. That's pretty clear but now what does she mean by drugs? 00:03:38.688 --> 00:03:44.836 Does she mean aspirin? I don't think she's telling you not to use aspirin. Does she 00:03:44.836 --> 00:03:50.335 mean prescription drugs? I don't think she's telling you not to follow the advice 00:03:50.335 --> 00:03:56.019 of your doctor and use the prescriptions that the doctor told you to take. So that 00:03:56.019 --> 00:04:03.960 can't be what she means. Well, maybe she means illegal drugs. Okay. Maybe she means 00:04:03.960 --> 00:04:08.679 illegal drugs. What about heroin or cocaine? Yes, that's what she is telling 00:04:08.679 --> 00:04:14.036 you not to do. She is definitely telling you not to take illegal drugs, but then 00:04:14.036 --> 00:04:19.329 there are some things in the middle. She might be telling you not to take dangerous 00:04:19.329 --> 00:04:24.240 drugs whether they are illegal or not. What about nicotine? What about alcohol? 00:04:24.240 --> 00:04:29.680 Those are both dangerous drugs, at least when you use in excess. Alcohol is very 00:04:29.680 --> 00:04:34.982 dangerous, and smoking can lead to lung cancer, and that's how most people get 00:04:34.982 --> 00:04:40.491 nicotine. So maybe she's telling you not to take nico tine or alcohol in addition 00:04:40.491 --> 00:04:46.000 to illegal drugs heroin and cocaine. Now it's not clear, so how do we clear it up? 00:04:46.000 --> 00:04:52.552 Well, you want Nancy Reagan's claim to look as good as possible. Remember, you're 00:04:52.552 --> 00:04:58.332 always trying to make the argument look as good as possible. And one way to make it 00:04:58.332 --> 00:05:05.005 look good is to make her claim no more than she has to claim. So, she could be 00:05:05.005 --> 00:05:10.100 claiming, in addition to heroin and cocaine, you shouldn't take alcohol and 00:05:10.100 --> 00:05:15.435 nicotine. But probably, or at least more plausibly, she's telling you not to take 00:05:15.435 --> 00:05:21.122 illegal drugs. She had to chose between interpreting her and saying don't take any 00:05:21.122 --> 00:05:26.393 illegal drugs and don't take any dangerous drugs. And it's seems like a more 00:05:26.393 --> 00:05:32.010 charitable interpretation that makes her claim look more plausible is don't take 00:05:32.010 --> 00:05:37.003 any illegal drugs. So we could clarify her claim, just say no to drugs, by 00:05:37.003 --> 00:05:42.566 interpreting it to mean you ought to not to take any illegal drugs. So in general 00:05:42.566 --> 00:05:47.671 then, the lesson is that, when there are options about how to clarify a certain 00:05:47.671 --> 00:05:52.383 sentence, we ought to pick the most charitable option that makes the claim 00:05:52.383 --> 00:05:58.047 look as good as possible. Here's another example, where the unclarity can be traced 00:05:58.047 --> 00:06:03.700 to a single word, but in this case it's the word that," and it's not clear what it 00:06:03.700 --> 00:06:09.424 refers to. So imagine that someone argues like this. Let's say, she claims, that our 00:06:09.424 --> 00:06:15.780 strategy won't work, because the enemy knows our plan, but that is a big mistake. 00:06:16.780 --> 00:06:24.940 What does that refer to? That could refer to, that is the word that could refer to 00:06:25.900 --> 00:06:30.787 that the enemy knows our plan. If someone says, that's a mistake, they might be 00:06:30.787 --> 00:06:36.072 saying, it's a mistake to think that the enemy knows our plan. But it could refer 00:06:36.072 --> 00:06:41.422 to the claim that our strategy won't work. They could be saying, it's a mistake to 00:06:41.422 --> 00:06:46.508 think our strategy won't work. Or, they could be saying that the mistake is to 00:06:46.508 --> 00:06:52.359 think that the enemy knowing our plan is enough to make it not work. He might be 00:06:52.359 --> 00:06:57.090 saying, it's not that it won't work because the enemy knows the plan. Or, 00:06:57.090 --> 00:07:02.354 here's a fourth possibility. He could be saying, that is a mistake to think that 00:07:02.354 --> 00:07:08.522 she claims that, that's not what she claims. So, there are four different ways 00:07:08.522 --> 00:07:15.096 to interpret, this argument, and in order to figure out how to interpret it, we have 00:07:15.096 --> 00:07:21.097 to figure out which of those is most likely as an interpretation of what the 00:07:21.097 --> 00:07:27.465 arguer is trying to say. And that's going to depend on which one makes the argument 00:07:27.465 --> 00:07:31.891 look the best. Now in this example it's not clear which interpretation is the 00:07:31.891 --> 00:07:36.095 best, because someone might give that argument in a context where they're saying 00:07:36.095 --> 00:07:40.300 the mistake is to think she claims that. But in other cases they might be saying 00:07:40.300 --> 00:07:44.347 that the mistake is to think that the enemy knows our plan. They don't really 00:07:44.347 --> 00:07:48.446 know our plan, and in other cases that might be claiming that other things are 00:07:48.446 --> 00:07:52.388 mistaken. So, we need to figure out what the person is saying, but that could 00:07:52.388 --> 00:07:56.945 depend on the particular context. It might vary from context to context. Now these 00:07:56.945 --> 00:08:03.217 unclarities seem unintentional. But sometimes people use unclearity to hide 00:08:03.217 --> 00:08:09.819 problems with their argument, to try to fool you. So imagine, a politician says we 00:08:09.819 --> 00:08:16.257 need to stop our enemies and stand by our friends, so we must remain strong and 00:08:16.257 --> 00:08:22.775 resolute. Well, if somebody starts arguing like that, you ought to be asking 00:08:22.775 --> 00:08:28.220 yourself, who do they think our friends are? Who do they think our enemies are? 00:08:28.220 --> 00:08:33.097 What do they mean, stop our enemies? Are they calling for military action? How do 00:08:33.097 --> 00:08:37.913 they think we ought to stop our enemies? And standing by our friends. Does that 00:08:37.913 --> 00:08:42.791 mean we ought to support'em, no matter what they do? There are lots of questions 00:08:42.791 --> 00:08:47.669 that you would want to ask, to clarify exactly which claim is being made before 00:08:47.669 --> 00:08:52.423 you accept something like this. Here's another claim that might be made by an 00:08:52.423 --> 00:08:57.240 opponent of the first politician. We have to help the needy. Well, wait a minute. 00:08:57.240 --> 00:09:02.246 Which people are needy? I mean everybody needs something. How needy to you have to 00:09:02.246 --> 00:09:07.315 be needy? And we ought to help the needy. Well how are we gonna help them? Does that 00:09:07.315 --> 00:09:12.075 mean we just give them what ever they want, or what are we suppose to give them? 00:09:12.075 --> 00:09:17.267 And when are we suppose to give them an d how much are we willing to spend on giving 00:09:17.267 --> 00:09:22.274 it to them? Politicians on both sides of the political spectrum make vague claims 00:09:22.274 --> 00:09:26.786 that need to clarified before you should be willing to endorse one or the other of 00:09:26.786 --> 00:09:32.408 those claims. If you try to decide what to believe before you know exactly what the 00:09:32.408 --> 00:09:37.915 claim means, before you've calrified it, you can end up commiting yourself to all 00:09:37.915 --> 00:09:43.009 kinds on nonsense and all kinds of very problematic positions. You can get 00:09:43.009 --> 00:09:48.171 yourself in to a lot of trouble. That's why we need to clarify the terms in 00:09:48.171 --> 00:09:53.424 arguments. Now, one special way in which premises need to be clarified, is that 00:09:53.424 --> 00:09:58.534 they need to be broken up into smaller parts, where you can do that. And the 00:09:58.534 --> 00:10:04.052 point of this, is that the smaller parts are going to be easier to understand, and 00:10:04.052 --> 00:10:09.298 easier to assess for whether they're true or not. So, step four, to clarify the 00:10:09.298 --> 00:10:14.726 premises, belongs together with step five, break up the premises into parts. What 00:10:14.726 --> 00:10:20.980 needs to be broken up? Well, the explicit premises and sometimes the conclusion as 00:10:20.980 --> 00:10:27.465 well. Here's a simple example. That shirt looks great on you and it's on sale, so 00:10:27.465 --> 00:10:34.752 you ought to buy it. We might put that in standard form like this. That shirt looks 00:10:34.752 --> 00:10:40.368 great on you and it's on sale is the premise and the conclusion is you ought to 00:10:40.368 --> 00:10:46.748 buy it. But notice that the premise has two parts, joined by an and. So we could 00:10:46.748 --> 00:10:52.900 break them up and have the first premise, that shirt looks great on you, and the 00:10:52.900 --> 00:10:58.740 second premise it's on sale and then the conclusion is you ought to buy it." 00:10:59.880 --> 00:11:05.243 Breaking up like that is supposed to make it easier to assess the premise for truth 00:11:05.243 --> 00:11:10.804 or falsehood. Now in this case it doesn't make it much easier cause it was so simple 00:11:10.804 --> 00:11:16.300 to begin with, but we'll see that breaking up premises will really help when we get 00:11:16.300 --> 00:11:21.464 to more complex examples. So, it makes sense to break up premises. Well, at least 00:11:21.464 --> 00:11:26.562 sometimes. We should not break up premises when breaking them up distorts the 00:11:26.562 --> 00:11:31.518 argument. Here's an example of that. We still need to add either one more cup 00:11:31.518 --> 00:11:37.253 white of suger, or one more cup of brown sugar to complete the recipe. So we've got 00:11:37.253 --> 00:11:43.198 to add another cup of ingredients. Now one way to represent that argument would be to 00:11:43.198 --> 00:11:48.794 say the premise is, we still need to add one more cup of white sugar, or one more 00:11:48.794 --> 00:11:54.600 cup of brown sugar, and the conclusion is, we have another cup of ingredients to add. 00:11:55.280 --> 00:12:00.585 But we can break it up cuz it's got parts. We can change the argument into we still 00:12:00.585 --> 00:12:05.699 need to add one more cup of white sugar. That's the first premise, and the second 00:12:05.699 --> 00:12:11.133 premise is we still need to add one cup of brown sugar. And then the conclusion is we 00:12:11.133 --> 00:12:16.311 have one more cup of ingredients to add, but that argument doesn't make any sense. 00:12:16.311 --> 00:12:21.552 If we've got to add one of white and one of brown, we don't just have one more cup 00:12:21.552 --> 00:12:26.730 of ingredients to add. And as always we're supposed to be making the argument look 00:12:26.730 --> 00:12:33.888 good and that change made it look bad. And the problem is that here we broke up the 00:12:33.888 --> 00:12:39.946 word or. Because it's one cup of white or one cup of brown and presumably you didn't 00:12:39.946 --> 00:12:44.967 know which it was, or maybe you had a choice between the two but you weren't 00:12:44.967 --> 00:12:50.119 suppose to add both. That would be too much, and the word or signals that. So in 00:12:50.119 --> 00:12:55.442 general, you should not break up when the word that joins the two is or, but it's 00:12:55.442 --> 00:13:00.851 okay to break up when the word that joins the two is and. You still got to be 00:13:00.851 --> 00:13:06.120 careful about context. It's not always goint to work that way, but as a general 00:13:06.120 --> 00:13:11.740 rule you know, that usually works. Other cases are even trickier. One particularly 00:13:11.740 --> 00:13:17.211 problematic case is dependent clauses. Here's an example. Nancy finished all her 00:13:17.211 --> 00:13:22.541 homework because all she had to do was write 25 lines of poetry, and she wrote 00:13:22.541 --> 00:13:28.502 two sonnets, which have fourteen lines each. The dependent clauses, which have 00:13:28.502 --> 00:13:34.653 fourteen lines each. And the question is, how do we fit that into standard form. 00:13:34.653 --> 00:13:40.172 Well, here's one stab. The first premise can say, all she had to do is write 25 00:13:40.172 --> 00:13:45.621 lines of poetry. And the second premise can be, she wrote two sonnets which have 00:13:45.621 --> 00:13:50.449 fourteen lines each. And then the conclusion is, Nancy finished all her 00:13:50.449 --> 00:13:56.753 homework. Now the question is can we break up that second premis e into two different 00:13:56.753 --> 00:14:01.729 parts? It seems like we can. We should be able to represent the argument. So the 00:14:01.729 --> 00:14:06.210 first premise is, all she had to do is write 25 lines of poetry and the second 00:14:06.210 --> 00:14:10.920 premise says she wrote two sonnets and the third premise is sonnets have fourteen 00:14:10.920 --> 00:14:15.310 lines each and the conclusion is she finished all her homework. In this case, 00:14:15.310 --> 00:14:20.226 breaking down the premise actually helps us understand and asses it. Because we can 00:14:20.226 --> 00:14:24.787 decide whether it's really true, for example, that sonnets have fourteen lines 00:14:24.787 --> 00:14:29.466 each. That's going to be a question. If the answer is no, then the argument might 00:14:29.466 --> 00:14:33.909 fail. The answer is yes, at least for standard sonnets. So the argument looks 00:14:33.909 --> 00:14:38.947 pretty good. Contrast that example with this one. Our legal system isn't fair 00:14:38.947 --> 00:14:44.019 because authorities go easy on white collar criminals who have been allowed to 00:14:44.019 --> 00:14:48.954 get away with their crimes in recent years. Well the premise, could be, 00:14:48.954 --> 00:14:54.556 authorities go easy on criminals who've been allowed to get away with their crimes 00:14:54.556 --> 00:14:59.618 in recent years. And, the conclusion is, our legal system isn't fair. Now the 00:14:59.618 --> 00:15:05.085 question is, can we break up that first premise, cuz it has the dependent clause, 00:15:05.085 --> 00:15:11.328 who've been allowed to get away with their crimes in recent years. Well that depends, 00:15:11.328 --> 00:15:17.235 because the person giving the argument might be saying that authorities go easy 00:15:17.235 --> 00:15:22.676 on all white collar criminals. And, they might be saying that authorities only go 00:15:22.676 --> 00:15:27.968 easy on a certain subset of white collar criminals, namely the subset they've been 00:15:27.968 --> 00:15:33.002 allowed to get away with their crimes in recent years. If the premises now all 00:15:33.002 --> 00:15:37.714 white collar criminals, then we can break it up so that one premises says 00:15:37.714 --> 00:15:42.812 authorities go easy on white collar criminals, and the next premise says white 00:15:42.812 --> 00:15:48.040 collar criminals have been allowed to get away with their crimes in recent years. 00:15:48.040 --> 00:15:52.640 But if the arguer is only talking about some white collar criminals, and admits 00:15:52.640 --> 00:15:57.591 that other white collar criminals have not been allowed to get away with their crime, 00:15:57.591 --> 00:16:02.133 then he's only saying that authorities go easy on those white collar criminals who 00:16:02.133 --> 00:16:06.501 have been allowed to get away with their crime, that subset of white collar 00:16:06.501 --> 00:16:11.277 criminals. And then it would distort the argument to break it up, because if you do 00:16:11.277 --> 00:16:16.111 break it up then that second premise says white collar criminals have been allowed 00:16:16.111 --> 00:16:21.677 to get away with their crimes in recent years. And if some of them haven't, then 00:16:21.677 --> 00:16:27.476 that premise turns out to be false. So if you break it up you can criticize it by 00:16:27.476 --> 00:16:32.415 pointing out that it doesn't really apply to all white collar criminals, but if you 00:16:32.415 --> 00:16:37.413 leave it as a single premise then it's not subject to that criticism, so if you want 00:16:37.413 --> 00:16:42.071 to be charitable, you probably ought to keep this premise together. Unless you 00:16:42.071 --> 00:16:47.126 know, on independent grounds, that the person was making that claim about all 00:16:47.126 --> 00:16:52.093 white collar criminals and not just a subset. So to make that argument look 00:16:52.093 --> 00:16:57.553 better we don't break up the premise and the general lesson is that with dependent 00:16:57.553 --> 00:17:02.881 clauses like that and with and who, you have to look very carefully to figure out 00:17:02.881 --> 00:17:08.209 what the speaker wanted to say and what's going to make their argument look best. 00:17:08.209 --> 00:17:13.471 And use that information to determine whether or not break up the premise. There 00:17:13.471 --> 00:17:18.865 are no air tight rules as always, so we need to do a few exercises to practice the