1 00:00:00,012 --> 00:00:04,657 This week, we're going to be talking about refutation. 2 00:00:04,657 --> 00:00:11,567 To refute an argument or to subject it to refutation, is to show that the argument 3 00:00:11,567 --> 00:00:16,427 is unsuccessful. The argument is invalid, or unsound, or 4 00:00:16,427 --> 00:00:20,737 commits one of the fallacies that we've described, 5 00:00:20,737 --> 00:00:27,072 but in any case, to refute the argument is to show that it's unsuccessful. 6 00:00:27,072 --> 00:00:32,222 Now, this week we'll be talking about four different methods of refutation, 7 00:00:32,222 --> 00:00:36,722 four different ways that you can show an argument is unsuccessful. 8 00:00:36,722 --> 00:00:41,672 In this lecture, we'll talk about counterexampling the argument, 9 00:00:41,672 --> 00:00:45,241 counterexamples. What's a counterexample? Well, a 10 00:00:45,241 --> 00:00:51,189 counterexample is an example that runs counter to some generalization. 11 00:00:51,189 --> 00:00:56,325 So, if someone puts forward a generalization, you can produce a 12 00:00:56,325 --> 00:01:02,484 counterexample to the generalization, an example that runs counter to the 13 00:01:02,484 --> 00:01:07,309 generalization in order to show that the generalization is not true. 14 00:01:07,309 --> 00:01:11,476 Now, some arguments contain generalization in their premises or 15 00:01:11,476 --> 00:01:16,204 contain a generalization in their conclusion, and if you counter example 16 00:01:16,204 --> 00:01:21,324 one or more of those generalization, you put forward a counterexample to one or 17 00:01:21,324 --> 00:01:26,419 more of those generalization, then you've shown that the arguement is no good. 18 00:01:26,419 --> 00:01:31,000 Either the conclusion, the conclusion generalization is not true 19 00:01:31,000 --> 00:01:36,080 or one of the premises, one of the premise generalizations is not true. 20 00:01:36,080 --> 00:01:41,082 But in any case, whether the conclusion is not true or whether one of the 21 00:01:41,082 --> 00:01:46,836 premises is not true, the argument itself is going to be at the very least unsound. 22 00:01:46,836 --> 00:01:52,281 Let me give you an example of an argument that contains a generalization in its 23 00:01:52,281 --> 00:01:59,260 conclusion and can be successfully counter exampled and thereby refuted. 24 00:01:59,260 --> 00:02:04,679 Consider the following display of information from the U.S. 25 00:02:04,679 --> 00:02:09,699 government. It indicates level of income and level of 26 00:02:09,699 --> 00:02:16,677 unemployment for people age 25 and over at different levels of educational 27 00:02:16,677 --> 00:02:20,017 attainment. So, depending on what level of 28 00:02:20,017 --> 00:02:24,853 educational attainment you have, the average income that you can expect per 29 00:02:24,853 --> 00:02:30,171 week and the average unemployment rate that you the average unemployment rate 30 00:02:30,171 --> 00:02:33,572 for people at that level of income is going to vary. 31 00:02:33,572 --> 00:02:41,520 Now, someone looking at the data represented by this chart might say, 32 00:02:41,520 --> 00:02:49,811 people with professional degrees make more money than people without a 33 00:02:49,811 --> 00:02:56,283 bachelors degree. People with professional degrees make 34 00:02:56,283 --> 00:03:00,132 more money than people with bachelor's degrees. 35 00:03:00,132 --> 00:03:05,975 Okay, now, if that generalization is understood to mean just that, on average, 36 00:03:05,975 --> 00:03:12,124 people with professional degrees make more money than people with bachelor's 37 00:03:12,124 --> 00:03:16,972 degrees, then in the United States for people over 25 today, 38 00:03:16,972 --> 00:03:22,852 that generalization is true. But if the generalization is understood 39 00:03:22,852 --> 00:03:29,662 to mean that all people with professional degrees make more money than any person 40 00:03:29,662 --> 00:03:33,295 with a bachelor's degree, then that claim can easily be 41 00:03:33,295 --> 00:03:37,487 counterexampled. And it can easily be counterexampled just 42 00:03:37,487 --> 00:03:42,972 by finding one person who has no higher educational attainment than a bachelor's 43 00:03:42,972 --> 00:03:48,165 degree, and then another person who has a professional degree, where the first 44 00:03:48,165 --> 00:03:52,082 person happens to make more money than the second person, 45 00:03:52,082 --> 00:03:56,939 and there are plenty of pairs of people like that, I can assure you. 46 00:03:56,939 --> 00:04:02,958 Let's consider another case in which we can refute an argument by means of 47 00:04:02,958 --> 00:04:06,669 counterexample. Suppose we consider the various cases in 48 00:04:06,669 --> 00:04:10,679 which we think it's wrong for someone to do something. 49 00:04:10,679 --> 00:04:16,697 Now, one thing that we'll notice that a lot of those cases have in common is that 50 00:04:16,697 --> 00:04:23,153 they're all cases in which it would be wrong for everyone to do that same thing. 51 00:04:23,153 --> 00:04:29,659 So for instance it would be wrong for everyone to engage in murder and so we 52 00:04:29,659 --> 00:04:34,498 think it's wrong for anybody to engage in murder. 53 00:04:34,498 --> 00:04:41,220 It would be wrong for everyone to lie and so we think it's wrong for anybody to 54 00:04:41,220 --> 00:04:44,802 lie. And it would be wrong for everyone to 55 00:04:44,802 --> 00:04:49,635 steal and so we thinks it's wrong for anybody to steal. 56 00:04:49,635 --> 00:04:53,652 Now, suppose that, when we survey these cases, 57 00:04:53,652 --> 00:04:58,784 we arrive at the general conclusion that whenever it's wrong for everyone to do 58 00:04:58,784 --> 00:05:02,137 something, it's gotta be wrong for anybody to do it. 59 00:05:02,137 --> 00:05:05,369 Now, that conclusion might seem plausible to you, 60 00:05:05,369 --> 00:05:10,096 especially when you keep in mind the examples that we've just considered. 61 00:05:10,096 --> 00:05:15,047 But now, think about a case where six of us are sitting around a table and we 62 00:05:15,047 --> 00:05:19,899 finished our dinner, and the plate of bread in the middle of the table, the 63 00:05:19,899 --> 00:05:24,705 plate of bread that was there for all of us to eat from has just one piece of 64 00:05:24,705 --> 00:05:27,962 bread left. Now, it would certainly be wrong for all 65 00:05:27,962 --> 00:05:32,860 of us to reach over and start fighting over that piece of bread, tugging at it 66 00:05:32,860 --> 00:05:36,722 from different angles, and tearing it apart selfishly? 67 00:05:36,722 --> 00:05:41,079 That would be wrong, but does that mean that it's wrong for 68 00:05:41,079 --> 00:05:44,378 anybody to take the bread? I don't think so. 69 00:05:44,378 --> 00:05:50,288 We don't have to leave a piece of bread on the table after we're all done eating, 70 00:05:50,288 --> 00:05:55,417 that would just be wasting food. It would be fine for one of us to take 71 00:05:55,417 --> 00:05:59,344 the bread. What's not fine is for the six of us to 72 00:05:59,344 --> 00:06:06,658 all fight over that last piece of bread. So, that example is a counterexample to 73 00:06:06,658 --> 00:06:14,080 the generalization that whenever it's wrong for everyone to do something, it's 74 00:06:14,080 --> 00:06:19,831 wrong for anyone to do that. So, if our survey of cases led us to 75 00:06:19,831 --> 00:06:24,235 conclude the truth of that generalization, then that argument was 76 00:06:24,235 --> 00:06:29,409 unsuccessful. That argument from the survey of cases that we surveyed earlier 77 00:06:29,409 --> 00:06:34,655 to the general conclusion that whenever it's wrong for everyone to do something, 78 00:06:34,655 --> 00:06:39,375 it's wrong for anyone to do it. That argument is unsuccessful and we can 79 00:06:39,375 --> 00:06:44,559 prove that it's unsuccessful by offering this counterexample to the conclusion.