1 00:00:02,380 --> 00:00:05,210 We're right in the middle of reconstruction. 2 00:00:05,210 --> 00:00:08,886 We did stage one last week, because that's just close analysis. 3 00:00:08,886 --> 00:00:13,703 In the previous section we did stage two, which is to remove excess verbiage, 4 00:00:13,703 --> 00:00:17,950 and to put the explicit premises and conclusion into standard form. 5 00:00:17,950 --> 00:00:22,704 And this lecture is going to focus on stage three, which is the clarify the 6 00:00:22,704 --> 00:00:27,078 premises and to break them up. Where it's possible without distorting 7 00:00:27,078 --> 00:00:29,867 them. Let's start with step four, which is to 8 00:00:29,867 --> 00:00:33,480 clarify the premises and the conclusion, when it's needed. 9 00:00:33,480 --> 00:00:39,217 So we might need to clarify them just in order to make them easier to understand, 10 00:00:39,217 --> 00:00:44,245 or to make them less likely to mislead, and all that sounds pretty good. 11 00:00:44,245 --> 00:00:50,373 So let's try on this example. It was hot today, so it'll probably be 12 00:00:50,373 --> 00:00:55,793 hot tomorrow again. And we need to clarify that. 13 00:00:55,793 --> 00:00:59,960 What exactly counts as today? Is that, 14 00:00:59,960 --> 00:01:05,552 you know, the time when there's daylight, or does it also include night, even 15 00:01:05,552 --> 00:01:09,893 though night is not day? And what exactly do we mean by hot? 16 00:01:09,893 --> 00:01:13,793 How hot was it today, and how hot will it be tomorrow? 17 00:01:13,793 --> 00:01:18,144 And what, after all, is heat? And what about, it'll probably be hot 18 00:01:18,144 --> 00:01:19,485 tomorrow? Probability. 19 00:01:19,485 --> 00:01:23,383 That's a tough notion. We're going to spend a whole week on that 20 00:01:23,383 --> 00:01:26,961 later on in the course. And there are different kinds of 21 00:01:26,961 --> 00:01:29,773 probability, and I want to know what kind you're 22 00:01:29,773 --> 00:01:33,415 talking about here. And when you ask for example, about it 23 00:01:33,415 --> 00:01:36,546 will be hot tomorrow, what is, what does will mean? 24 00:01:36,546 --> 00:01:41,146 It means it's going to happen in the future, and what exactly is the future? 25 00:01:41,146 --> 00:01:43,447 And is the future real? Is time real? 26 00:01:43,447 --> 00:01:48,367 You can go a long way towards asking how to clarify that argument. But that's 27 00:01:48,367 --> 00:01:51,717 ridiculous, you know. We don't have to clarify a 28 00:01:51,717 --> 00:01:57,160 simple argument like it was hot today so it will probably be hot tomorrow. 29 00:01:57,160 --> 00:02:01,760 And it's lucky we don't have to clarify every word in the argument because we 30 00:02:01,760 --> 00:02:05,948 couldn't because after all when you explain one of the words or give a 31 00:02:05,948 --> 00:02:10,549 definition for it, it's going to be in terms of other words and then they have 32 00:02:10,549 --> 00:02:14,324 to get clarified and you'll never going to get to the end of it. 33 00:02:14,324 --> 00:02:18,335 The search for perfect clarity and absolute precision is impossible. 34 00:02:18,335 --> 00:02:22,523 You'll never complete that search. You'll never find perfect clarity or 35 00:02:22,523 --> 00:02:26,886 absolute precision, so give it up. What we should seek is not absolute 36 00:02:26,886 --> 00:02:31,384 precision, but adequate precision. Not absolute clarity, but adequate 37 00:02:31,384 --> 00:02:34,473 clarity. And that means that we ought to try to 38 00:02:34,473 --> 00:02:39,776 clear up those parts of the premises and conclusion that are likely to produce 39 00:02:39,776 --> 00:02:42,999 confusion later. And you have to be able to kind of 40 00:02:42,999 --> 00:02:48,571 predict whether this part of the argument needs to be clarified, because people are 41 00:02:48,571 --> 00:02:52,319 going to get confused by it. Now that's not going to be easy, 42 00:02:52,319 --> 00:02:56,845 and there's no simple or mechanical rule to tell you what needs to be clarified, 43 00:02:56,845 --> 00:03:02,406 and what doesn't need to be clarified. The only way to learn this skill is to go 44 00:03:02,406 --> 00:03:07,709 through some examples that will give you models of what needs to be clarified and 45 00:03:07,709 --> 00:03:11,717 what doesn't. Sometimes, you know, in clarity lies in a 46 00:03:11,717 --> 00:03:15,756 single word. In the 1980's Nancy Reagan used to say, 47 00:03:15,756 --> 00:03:19,401 just say no to drugs. What does that mean? 48 00:03:19,401 --> 00:03:25,561 Well, she is telling you not to use drugs, to say no when somebody offers you 49 00:03:25,561 --> 00:03:32,046 drugs or tries to tell you to use drugs. So, in effect, she's saying you ought not 50 00:03:32,046 --> 00:03:37,496 to use drugs. That's pretty clear but now what does she 51 00:03:37,496 --> 00:03:40,763 mean by drugs? Does she mean aspirin? 52 00:03:40,763 --> 00:03:44,225 I don't think she's telling you not to use aspirin. 53 00:03:44,225 --> 00:03:49,113 Does she mean prescription drugs? I don't think she's telling you not to 54 00:03:49,113 --> 00:03:54,545 follow the advice of your doctor and use the prescriptions that the doctor told 55 00:03:54,545 --> 00:03:57,998 you to take. So that can't be what she means. 56 00:03:57,998 --> 00:04:02,940 Well, maybe she means illegal drugs. Okay. 57 00:04:02,940 --> 00:04:06,702 Maybe she means illegal drugs. What about heroin or cocaine? 58 00:04:06,702 --> 00:04:09,891 Yes, that's what she is telling you not to do. 59 00:04:09,891 --> 00:04:14,992 She is definitely telling you not to take illegal drugs, but then there are some 60 00:04:14,992 --> 00:04:18,691 things in the middle. She might be telling you not to take 61 00:04:18,691 --> 00:04:21,752 dangerous drugs whether they are illegal or not. 62 00:04:21,752 --> 00:04:24,240 What about nicotine? What about alcohol? 63 00:04:24,240 --> 00:04:28,578 Those are both dangerous drugs, at least when you use in excess. 64 00:04:28,578 --> 00:04:33,880 Alcohol is very dangerous, and smoking can lead to lung cancer, and that's how 65 00:04:33,880 --> 00:04:38,287 most people get nicotine. So maybe she's telling you not to take 66 00:04:38,287 --> 00:04:42,970 nicotine or alcohol in addition to illegal drugs heroin and cocaine. 67 00:04:42,970 --> 00:04:46,000 Now it's not clear, so how do we clear it up? 68 00:04:46,000 --> 00:04:50,254 Well, you want Nancy Reagan's claim to look as 69 00:04:50,254 --> 00:04:54,084 good as possible. Remember, you're always trying to make 70 00:04:54,084 --> 00:04:59,446 the argument look as good as possible. And one way to make it look good is to 71 00:04:59,446 --> 00:05:02,580 make her claim no more than she has to claim. 72 00:05:02,580 --> 00:05:06,657 So, she could be claiming, in addition to 73 00:05:06,657 --> 00:05:10,720 heroin and cocaine, you shouldn't take alcohol and nicotine. 74 00:05:10,720 --> 00:05:15,990 But probably, or at least more plausibly, she's telling you not to take illegal 75 00:05:15,990 --> 00:05:19,319 drugs. She had to chose between interpreting her 76 00:05:19,319 --> 00:05:24,520 and saying don't take any illegal drugs and don't take any dangerous drugs. 77 00:05:24,520 --> 00:05:29,999 And it's seems like a more charitable interpretation that makes her claim look 78 00:05:29,999 --> 00:05:33,258 more plausible is don't take any illegal drugs. 79 00:05:33,258 --> 00:05:38,667 So we could clarify her claim, just say no to drugs, by interpreting it to mean 80 00:05:38,667 --> 00:05:41,650 you ought to not to take any illegal drugs. 81 00:05:41,650 --> 00:05:46,493 So in general then, the lesson is that, when there are options about how to 82 00:05:46,493 --> 00:05:51,336 clarify a certain sentence, we ought to pick the most charitable option that 83 00:05:51,336 --> 00:05:56,351 makes the claim look as good as possible. Here's another example, where the 84 00:05:56,351 --> 00:06:02,075 unclarity can be traced to a single word, but in this case it's the word that," and 85 00:06:02,075 --> 00:06:07,304 it's not clear what it refers to. So imagine that someone argues like this. 86 00:06:07,304 --> 00:06:12,816 Let's say, she claims, that our strategy won't work, because the enemy knows our 87 00:06:12,816 --> 00:06:16,780 plan, but that is a big mistake. 88 00:06:16,780 --> 00:06:22,925 What does that refer to? That could refer to, that is the word 89 00:06:22,925 --> 00:06:27,881 that could refer to that the enemy knows our plan. 90 00:06:27,881 --> 00:06:32,835 If someone says, that's a mistake, they might be saying, it's a mistake to think 91 00:06:32,835 --> 00:06:37,525 that the enemy knows our plan. But it could refer to the claim that our 92 00:06:37,525 --> 00:06:41,422 strategy won't work. They could be saying, it's a mistake to 93 00:06:41,422 --> 00:06:46,112 think our strategy won't work. Or, they could be saying that the mistake 94 00:06:46,112 --> 00:06:51,560 is to think that the enemy knowing our plan is enough to make it not work. 95 00:06:51,560 --> 00:06:56,557 He might be saying, it's not that it won't work because the enemy knows the 96 00:06:56,557 --> 00:06:58,956 plan. Or, here's a fourth possibility. 97 00:06:58,956 --> 00:07:04,153 He could be saying, that is a mistake to think that she claims that, that's not 98 00:07:04,153 --> 00:07:08,784 what she claims. So, there are four different ways to 99 00:07:08,784 --> 00:07:13,486 interpret, this argument, and in order to figure out how to 100 00:07:13,486 --> 00:07:18,947 interpret it, we have to figure out which of those is most likely as an 101 00:07:18,947 --> 00:07:23,007 interpretation of what the arguer is trying to say. 102 00:07:23,007 --> 00:07:28,580 And that's going to depend on which one makes the argument look the best. 103 00:07:28,580 --> 00:07:32,153 Now in this example it's not clear which interpretation is the best, 104 00:07:32,153 --> 00:07:36,305 because someone might give that argument in a context where they're saying the 105 00:07:36,305 --> 00:07:40,300 mistake is to think she claims that. But in other cases they might be saying 106 00:07:40,300 --> 00:07:43,401 that the mistake is to think that the enemy knows our plan. 107 00:07:43,401 --> 00:07:47,290 They don't really know our plan, and in other cases that might be claiming 108 00:07:47,290 --> 00:07:51,074 that other things are mistaken. So, we need to figure out what the person 109 00:07:51,074 --> 00:07:53,702 is saying, but that could depend on the particular 110 00:07:53,702 --> 00:07:56,120 context. It might vary from context to context. 111 00:07:56,120 --> 00:08:02,804 Now these unclarities seem unintentional. But sometimes people use unclearity to 112 00:08:02,804 --> 00:08:07,178 hide problems with their argument, to try to fool you. 113 00:08:07,178 --> 00:08:13,286 So imagine, a politician says we need to stop our enemies and stand by our 114 00:08:13,286 --> 00:08:17,000 friends, so we must remain strong and resolute. 115 00:08:18,320 --> 00:08:23,411 Well, if somebody starts arguing like that, you ought to be asking yourself, 116 00:08:23,411 --> 00:08:28,220 who do they think our friends are? Who do they think our enemies are? 117 00:08:28,220 --> 00:08:32,665 What do they mean, stop our enemies? Are they calling for military action? 118 00:08:32,665 --> 00:08:35,567 How do they think we ought to stop our enemies? 119 00:08:35,567 --> 00:08:39,828 And standing by our friends. Does that mean we ought to support'em, no 120 00:08:39,828 --> 00:08:43,347 matter what they do? There are lots of questions that you 121 00:08:43,347 --> 00:08:47,916 would want to ask, to clarify exactly which claim is being made before you 122 00:08:47,916 --> 00:08:52,053 accept something like this. Here's another claim that might be made 123 00:08:52,053 --> 00:08:56,066 by an opponent of the first politician. We have to help the needy. 124 00:08:56,066 --> 00:08:58,661 Well, wait a minute. Which people are needy? 125 00:08:58,661 --> 00:09:02,803 I mean everybody needs something. How needy to you have to be needy? 126 00:09:02,803 --> 00:09:06,697 And we ought to help the needy. Well how are we going to help them? 127 00:09:06,697 --> 00:09:11,456 Does that mean we just give them what ever they want, or what are we suppose to 128 00:09:11,456 --> 00:09:14,609 give them? And when are we suppose to give them and 129 00:09:14,609 --> 00:09:17,947 how much are we willing to spend on giving it to them? 130 00:09:17,947 --> 00:09:22,583 Politicians on both sides of the political spectrum make vague claims that 131 00:09:22,583 --> 00:09:26,786 need to clarified before you should be willing to endorse one or the other of 132 00:09:26,786 --> 00:09:30,136 those claims. If you try to decide what to believe 133 00:09:30,136 --> 00:09:35,368 before you know exactly what the claim means, before you've calrified it, you 134 00:09:35,368 --> 00:09:40,668 can end up commiting yourself to all kinds on nonsense and all kinds of very 135 00:09:40,668 --> 00:09:45,211 problematic positions. You can get yourself in to a lot of trouble. 136 00:09:45,211 --> 00:09:48,860 That's why we need to clarify the terms in arguments. 137 00:09:48,860 --> 00:09:54,105 Now, one special way in which premises need to be clarified, is that they need 138 00:09:54,105 --> 00:09:57,989 to be broken up into smaller parts, where you can do that. 139 00:09:57,989 --> 00:10:03,030 And the point of this, is that the smaller parts are going to be easier to 140 00:10:03,030 --> 00:10:07,390 understand, and easier to assess for whether they're true or not. 141 00:10:07,390 --> 00:10:12,704 So, step four, to clarify the premises, belongs together with step five, break up 142 00:10:12,704 --> 00:10:16,424 the premises into parts. What needs to be broken up? 143 00:10:16,424 --> 00:10:21,366 Well, the explicit premises and sometimes the conclusion as well. 144 00:10:21,366 --> 00:10:26,828 Here's a simple example. That shirt looks great on you and it's on 145 00:10:26,828 --> 00:10:33,208 sale, so you ought to buy it. We might put that in standard form like 146 00:10:33,208 --> 00:10:36,507 this. That shirt looks great on you and it's on 147 00:10:36,507 --> 00:10:41,220 sale is the premise and the conclusion is you ought to buy it. 148 00:10:41,220 --> 00:10:45,814 But notice that the premise has two parts, joined by an and. 149 00:10:45,814 --> 00:10:51,965 So we could break them up and have the first premise, that shirt looks great on 150 00:10:51,965 --> 00:10:58,194 you, and the second premise it's on sale and then the conclusion is you ought to 151 00:10:58,194 --> 00:11:04,051 buy it." Breaking up like that is supposed to make it easier to assess the 152 00:11:04,051 --> 00:11:08,818 premise for truth or falsehood. Now in this case it doesn't make it much 153 00:11:08,818 --> 00:11:13,784 easier cause it was so simple to begin with, but we'll see that breaking up 154 00:11:13,784 --> 00:11:17,955 premises will really help when we get to more complex examples. 155 00:11:17,955 --> 00:11:22,060 So, it makes sense to break up premises. Well, at least sometimes. 156 00:11:22,060 --> 00:11:27,158 We should not break up premises when breaking them up distorts the argument. 157 00:11:27,158 --> 00:11:31,518 Here's an example of that. We still need to add either one more cup 158 00:11:31,518 --> 00:11:36,344 white of suger, or one more cup of brown sugar to complete the recipe. 159 00:11:36,344 --> 00:11:39,631 So we've got to add another cup of ingredients. 160 00:11:39,631 --> 00:11:45,157 Now one way to represent that argument would be to say the premise is, we still 161 00:11:45,157 --> 00:11:50,683 need to add one more cup of white sugar, or one more cup of brown sugar, and the 162 00:11:50,683 --> 00:11:55,280 conclusion is, we have another cup of ingredients to add. 163 00:11:55,280 --> 00:11:57,964 But we can break it up because it's got parts. 164 00:11:57,964 --> 00:12:03,142 We can change the argument into we still need to add one more cup of white sugar. 165 00:12:03,142 --> 00:12:07,297 That's the first premise, and the second premise is we still need 166 00:12:07,297 --> 00:12:11,708 to add one cup of brown sugar. And then the conclusion is we have one 167 00:12:11,708 --> 00:12:16,311 more cup of ingredients to add, but that argument doesn't make any sense. 168 00:12:16,311 --> 00:12:19,507 If we've got to add one of white and one of brown, 169 00:12:19,507 --> 00:12:22,959 we don't just have one more cup of ingredients to add. 170 00:12:22,959 --> 00:12:28,073 And as always we're supposed to be making the argument look good and that change 171 00:12:28,073 --> 00:12:33,567 made it look bad. And the problem is that here we broke up 172 00:12:33,567 --> 00:12:37,238 the word or. Because it's one cup of white or one cup 173 00:12:37,238 --> 00:12:42,853 of brown and presumably you didn't know which it was, or maybe you had a choice 174 00:12:42,853 --> 00:12:46,288 between the two but you weren't suppose to add both. 175 00:12:46,288 --> 00:12:49,723 That would be too much, and the word or signals that. 176 00:12:49,723 --> 00:12:54,810 So in general, you should not break up when the word that joins the two is or, 177 00:12:54,810 --> 00:12:59,446 but it's okay to break up when the word that joins the two is and. 178 00:12:59,446 --> 00:13:02,397 You still got to be careful about context. 179 00:13:02,397 --> 00:13:07,455 It's not always goint to work that way, but as a general rule you know, that 180 00:13:07,455 --> 00:13:10,546 usually works. Other cases are even trickier. 181 00:13:10,546 --> 00:13:14,410 One particularly problematic case is dependent clauses. 182 00:13:14,410 --> 00:13:18,373 Here's an example. Nancy finished all her homework because 183 00:13:18,373 --> 00:13:23,771 all she had to do was write 25 lines of poetry, and she wrote two sonnets, which 184 00:13:23,771 --> 00:13:28,502 have fourteen lines each. The dependent clauses, which have 185 00:13:28,502 --> 00:13:33,155 fourteen lines each. And the question is, how do we fit that 186 00:13:33,155 --> 00:13:36,310 into standard form. Well, here's one stab. 187 00:13:36,310 --> 00:13:41,275 The first premise can say, all she had to do is write 25 lines of poetry. 188 00:13:41,275 --> 00:13:46,655 And the second premise can be, she wrote two sonnets which have fourteen lines 189 00:13:46,655 --> 00:13:49,276 each. And then the conclusion is, Nancy 190 00:13:49,276 --> 00:13:54,177 finished all her homework. Now the question is can we break up that 191 00:13:54,177 --> 00:13:58,800 second premise into two different parts? It seems like we can. 192 00:13:58,800 --> 00:14:01,327 We should be able to represent the argument. 193 00:14:01,327 --> 00:14:05,808 So the first premise is, all she had to do is write 25 lines of poetry and the 194 00:14:05,808 --> 00:14:10,403 second premise says she wrote two sonnets and the third premise is sonnets have 195 00:14:10,403 --> 00:14:14,540 fourteen lines each and the conclusion is she finished all her homework. 196 00:14:14,540 --> 00:14:19,160 In this case, breaking down the premise actually helps us understand and asses 197 00:14:19,160 --> 00:14:21,825 it. Because we can decide whether it's really 198 00:14:21,825 --> 00:14:25,083 true, for example, that sonnets have fourteen lines each. 199 00:14:25,083 --> 00:14:29,111 That's going to be a question. If the answer is no, then the argument 200 00:14:29,111 --> 00:14:32,132 might fail. The answer is yes, at least for standard 201 00:14:32,132 --> 00:14:34,620 sonnets. So the argument looks pretty good. 202 00:14:34,620 --> 00:14:39,461 Contrast that example with this one. Our legal system isn't fair because 203 00:14:39,461 --> 00:14:44,276 authorities go easy on white collar criminals who have been allowed to get 204 00:14:44,276 --> 00:14:48,954 away with their crimes in recent years. Well the premise, could be, 205 00:14:48,954 --> 00:14:54,084 authorities go easy on criminals who've been allowed to get away with their 206 00:14:54,084 --> 00:14:58,268 crimes in recent years. And, the conclusion is, our legal system 207 00:14:58,268 --> 00:15:01,845 isn't fair. Now the question is, can we break up that 208 00:15:01,845 --> 00:15:05,085 first premise, because it has the dependent clause, 209 00:15:05,085 --> 00:15:10,000 who've been allowed to get away with their crimes in recent years. 210 00:15:10,000 --> 00:15:15,758 Well that depends, because the person giving the argument might be saying that 211 00:15:15,758 --> 00:15:19,450 authorities go easy on all white collar criminals. 212 00:15:19,450 --> 00:15:23,838 And, they might be saying that authorities only go easy on a certain 213 00:15:23,838 --> 00:15:28,936 subset of white collar criminals, namely the subset they've been allowed to get 214 00:15:28,936 --> 00:15:33,841 away with their crimes in recent years. If the premises now all white collar 215 00:15:33,841 --> 00:15:38,682 criminals, then we can break it up so that one premises says authorities go 216 00:15:38,682 --> 00:15:43,264 easy on white collar criminals, and the next premise says white collar 217 00:15:43,264 --> 00:15:48,040 criminals have been allowed to get away with their crimes in recent years. 218 00:15:48,040 --> 00:15:52,640 But if the arguer is only talking about some white collar criminals, and admits 219 00:15:52,640 --> 00:15:57,241 that other white collar criminals have not been allowed to get away with their 220 00:15:57,241 --> 00:16:01,318 crime, then he's only saying that authorities go easy on those white collar 221 00:16:01,318 --> 00:16:05,744 criminals who have been allowed to get away with their crime, that subset of 222 00:16:05,744 --> 00:16:09,530 white collar criminals. And then it would distort the argument to 223 00:16:09,530 --> 00:16:14,072 break it up, because if you do break it up then that second premise says white 224 00:16:14,072 --> 00:16:18,790 collar criminals have been allowed to get away with their crimes in recent years. 225 00:16:18,790 --> 00:16:24,740 And if some of them haven't, then that premise turns out to be false. 226 00:16:24,740 --> 00:16:29,618 So if you break it up you can criticize it by pointing out that it doesn't really 227 00:16:29,618 --> 00:16:34,438 apply to all white collar criminals, but if you leave it as a single premise then 228 00:16:34,438 --> 00:16:39,198 it's not subject to that criticism, so if you want to be charitable, you probably 229 00:16:39,198 --> 00:16:43,934 ought to keep this premise together. Unless you know, on independent grounds, 230 00:16:43,934 --> 00:16:49,188 that the person was making that claim about all white collar criminals and not 231 00:16:49,188 --> 00:16:52,751 just a subset. So to make that argument look better we 232 00:16:52,751 --> 00:16:57,553 don't break up the premise and the general lesson is that with dependent 233 00:16:57,553 --> 00:17:02,881 clauses like that and with and who, you have to look very carefully to figure out 234 00:17:02,881 --> 00:17:08,209 what the speaker wanted to say and what's going to make their argument look best. 235 00:17:08,209 --> 00:17:13,076 And use that information to determine whether or not break up the premise. 236 00:17:13,076 --> 00:17:18,010 There are no air tight rules as always, so we need to do a few exercises to 237 00:17:18,010 --> 00:17:19,260 practice the skill.