1 00:00:00,148 --> 00:00:03,530 I'm going to talk to you about optimism -- 2 00:00:03,530 --> 00:00:06,013 or more precisely, the optimism bias. 3 00:00:06,013 --> 00:00:07,658 It's a cognitive illusion 4 00:00:07,658 --> 00:00:10,400 that we've been studying in my lab for the past few years, 5 00:00:10,400 --> 00:00:12,135 and 80 percent of us have it. 6 00:00:12,135 --> 00:00:14,869 It's our tendency to overestimate 7 00:00:14,869 --> 00:00:17,792 our likelihood of experiencing good events in our lives 8 00:00:17,792 --> 00:00:21,900 and underestimate our likelihood of experiencing bad events. 9 00:00:21,900 --> 00:00:24,917 So we underestimate our likelihood of suffering from cancer, 10 00:00:24,917 --> 00:00:26,423 being in a car accident. 11 00:00:26,423 --> 00:00:29,609 We overestimate our longevity, our career prospects. 12 00:00:29,609 --> 00:00:33,054 In short, we're more optimistic than realistic, 13 00:00:33,054 --> 00:00:35,216 but we are oblivious to the fact. 14 00:00:35,216 --> 00:00:37,443 Take marriage for example. 15 00:00:37,443 --> 00:00:40,977 In the Western world, divorce rates are about 40 percent. 16 00:00:40,977 --> 00:00:44,446 That means that out of five married couples, 17 00:00:44,446 --> 00:00:47,167 two will end up splitting their assets. 18 00:00:47,167 --> 00:00:50,542 But when you ask newlyweds about their own likelihood of divorce, 19 00:00:50,542 --> 00:00:54,234 they estimate it at zero percent. 20 00:00:54,234 --> 00:00:57,963 And even divorce lawyers, who should really know better, 21 00:00:57,963 --> 00:01:01,812 hugely underestimate their own likelihood of divorce. 22 00:01:01,812 --> 00:01:04,938 So it turns out that optimists are not less likely to divorce, 23 00:01:04,938 --> 00:01:07,468 but they are more likely to remarry. 24 00:01:07,468 --> 00:01:09,771 In the words of Samuel Johnson, 25 00:01:09,771 --> 00:01:13,768 "Remarriage is the triumph of hope over experience." 26 00:01:13,768 --> 00:01:15,730 (Laughter) 27 00:01:15,730 --> 00:01:20,304 So if we're married, we're more likely to have kids. 28 00:01:20,304 --> 00:01:23,569 And we all think our kids will be especially talented. 29 00:01:23,569 --> 00:01:26,167 This, by the way, is my two-year-old nephew, Guy. 30 00:01:26,167 --> 00:01:28,542 And I just want to make it absolutely clear 31 00:01:28,542 --> 00:01:31,313 that he's a really bad example of the optimism bias, 32 00:01:31,313 --> 00:01:34,125 because he is in fact uniquely talented. 33 00:01:34,125 --> 00:01:35,560 (Laughter) 34 00:01:35,560 --> 00:01:37,167 And I'm not alone. 35 00:01:37,167 --> 00:01:39,642 Out of four British people, three said 36 00:01:39,642 --> 00:01:43,381 that they were optimistic about the future of their own families. 37 00:01:43,381 --> 00:01:45,132 That's 75 percent. 38 00:01:45,132 --> 00:01:47,190 But only 30 percent said 39 00:01:47,190 --> 00:01:49,750 that they thought families in general 40 00:01:49,750 --> 00:01:52,162 are doing better than a few generations ago. 41 00:01:52,162 --> 00:01:54,183 And this is a really important point, 42 00:01:54,183 --> 00:01:56,071 because we're optimistic about ourselves, 43 00:01:56,071 --> 00:01:57,889 we're optimistic about our kids, 44 00:01:57,889 --> 00:01:59,677 we're optimistic about our families, 45 00:01:59,677 --> 00:02:02,860 but we're not so optimistic about the guy sitting next to us, 46 00:02:02,860 --> 00:02:05,089 and we're somewhat pessimistic 47 00:02:05,089 --> 00:02:08,968 about the fate of our fellow citizens and the fate of our country. 48 00:02:08,968 --> 00:02:13,004 But private optimism about our own personal future 49 00:02:13,004 --> 00:02:15,015 remains persistent. 50 00:02:15,015 --> 00:02:19,081 And it doesn't mean that we think things will magically turn out okay, 51 00:02:19,081 --> 00:02:23,113 but rather that we have the unique ability to make it so. 52 00:02:23,113 --> 00:02:25,954 Now I'm a scientist, I do experiments. 53 00:02:25,954 --> 00:02:27,746 So to show you what I mean, 54 00:02:27,746 --> 00:02:30,548 I'm going to do an experiment here with you. 55 00:02:30,548 --> 00:02:34,398 So I'm going to give you a list of abilities and characteristics, 56 00:02:34,398 --> 00:02:37,292 and I want you to think for each of these abilities 57 00:02:37,292 --> 00:02:41,685 where you stand relative to the rest of the population. 58 00:02:41,685 --> 00:02:45,471 The first one is getting along well with others. 59 00:02:45,471 --> 00:02:51,123 Who here believes they're at the bottom 25 percent? 60 00:02:51,123 --> 00:02:55,445 Okay, that's about 10 people out of 1,500. 61 00:02:55,445 --> 00:02:59,458 Who believes they're at the top 25 percent? 62 00:02:59,458 --> 00:03:02,168 That's most of us here. 63 00:03:02,168 --> 00:03:07,098 Okay, now do the same for your driving ability. 64 00:03:07,098 --> 00:03:09,681 How interesting are you? 65 00:03:09,681 --> 00:03:12,525 How attractive are you? 66 00:03:12,525 --> 00:03:15,479 How honest are you? 67 00:03:15,479 --> 00:03:20,479 And finally, how modest are you? 68 00:03:20,479 --> 00:03:23,167 So most of us put ourselves above average 69 00:03:23,167 --> 00:03:25,196 on most of these abilities. 70 00:03:25,196 --> 00:03:27,327 Now this is statistically impossible. 71 00:03:27,327 --> 00:03:30,556 We can't all be better than everyone else. 72 00:03:30,556 --> 00:03:32,198 (Laughter) 73 00:03:32,198 --> 00:03:34,875 But if we believe we're better than the other guy, 74 00:03:34,875 --> 00:03:38,958 well that means that we're more likely to get that promotion, to remain married, 75 00:03:38,958 --> 00:03:41,556 because we're more social, more interesting. 76 00:03:41,556 --> 00:03:43,719 And it's a global phenomenon. 77 00:03:43,719 --> 00:03:46,187 The optimism bias has been observed 78 00:03:46,187 --> 00:03:47,906 in many different countries -- 79 00:03:47,906 --> 00:03:51,010 in Western cultures, in non-Western cultures, 80 00:03:51,010 --> 00:03:52,516 in females and males, 81 00:03:52,516 --> 00:03:54,240 in kids, in the elderly. 82 00:03:54,240 --> 00:03:56,023 It's quite widespread. 83 00:03:56,023 --> 00:03:59,523 But the question is, is it good for us? 84 00:03:59,523 --> 00:04:01,977 So some people say no. 85 00:04:01,977 --> 00:04:04,495 Some people say the secret to happiness 86 00:04:04,495 --> 00:04:07,248 is low expectations. 87 00:04:07,248 --> 00:04:09,752 I think the logic goes something like this: 88 00:04:09,752 --> 00:04:12,010 If we don't expect greatness, 89 00:04:12,010 --> 00:04:15,890 if we don't expect to find love and be healthy and successful, 90 00:04:15,890 --> 00:04:18,988 well we're not going to be disappointed when these things don't happen. 91 00:04:18,988 --> 00:04:22,396 And if we're not disappointed when good things don't happen, 92 00:04:22,396 --> 00:04:24,375 and we're pleasantly surprised when they do, 93 00:04:24,375 --> 00:04:26,156 we will be happy. 94 00:04:26,156 --> 00:04:27,858 So it's a very good theory, 95 00:04:27,858 --> 00:04:30,885 but it turns out to be wrong for three reasons. 96 00:04:30,885 --> 00:04:35,500 Number one: Whatever happens, whether you succeed or you fail, 97 00:04:35,500 --> 00:04:39,358 people with high expectations always feel better. 98 00:04:39,358 --> 00:04:43,290 Because how we feel when we get dumped or win employee of the month 99 00:04:43,290 --> 00:04:46,320 depends on how we interpret that event. 100 00:04:46,320 --> 00:04:50,370 The psychologists Margaret Marshall and John Brown 101 00:04:50,370 --> 00:04:53,364 studied students with high and low expectations. 102 00:04:53,364 --> 00:04:57,548 And they found that when people with high expectations succeed, 103 00:04:57,548 --> 00:05:00,458 they attribute that success to their own traits. 104 00:05:00,458 --> 00:05:02,654 "I'm a genius, therefore I got an A, 105 00:05:02,654 --> 00:05:05,329 therefore I'll get an A again and again in the future." 106 00:05:05,329 --> 00:05:08,302 When they failed, it wasn't because they were dumb, 107 00:05:08,302 --> 00:05:11,475 but because the exam just happened to be unfair. 108 00:05:11,475 --> 00:05:13,758 Next time they will do better. 109 00:05:13,758 --> 00:05:16,835 People with low expectations do the opposite. 110 00:05:16,835 --> 00:05:19,667 So when they failed it was because they were dumb, 111 00:05:19,667 --> 00:05:21,167 and when they succeeded 112 00:05:21,167 --> 00:05:24,484 it was because the exam just happened to be really easy. 113 00:05:24,484 --> 00:05:26,885 Next time reality would catch up with them. 114 00:05:26,885 --> 00:05:28,958 So they felt worse. 115 00:05:28,958 --> 00:05:32,198 Number two: Regardless of the outcome, 116 00:05:32,198 --> 00:05:36,245 the pure act of anticipation makes us happy. 117 00:05:36,245 --> 00:05:39,421 The behavioral economist George Lowenstein 118 00:05:39,421 --> 00:05:41,140 asked students in his university 119 00:05:41,140 --> 00:05:45,502 to imagine getting a passionate kiss from a celebrity, any celebrity. 120 00:05:45,502 --> 00:05:48,387 Then he said, "How much are you willing to pay 121 00:05:48,387 --> 00:05:50,375 to get a kiss from a celebrity 122 00:05:50,375 --> 00:05:52,602 if the kiss was delivered immediately, 123 00:05:52,602 --> 00:05:57,625 in three hours, in 24 hours, in three days, 124 00:05:57,625 --> 00:06:00,058 in one year, in 10 years? 125 00:06:00,058 --> 00:06:03,188 He found that the students were willing to pay the most 126 00:06:03,188 --> 00:06:05,187 not to get a kiss immediately, 127 00:06:05,187 --> 00:06:08,167 but to get a kiss in three days. 128 00:06:08,167 --> 00:06:12,414 They were willing to pay extra in order to wait. 129 00:06:12,414 --> 00:06:15,417 Now they weren't willing to wait a year or 10 years; 130 00:06:15,417 --> 00:06:16,838 no one wants an aging celebrity. 131 00:06:16,838 --> 00:06:21,627 But three days seemed to be the optimum amount. 132 00:06:21,627 --> 00:06:23,930 So why is that? 133 00:06:23,930 --> 00:06:27,354 Well if you get the kiss now, it's over and done with. 134 00:06:27,354 --> 00:06:29,304 But if you get the kiss in three days, 135 00:06:29,304 --> 00:06:33,458 well that's three days of jittery anticipation, the thrill of the wait. 136 00:06:33,458 --> 00:06:35,327 The students wanted that time 137 00:06:35,327 --> 00:06:37,708 to imagine where is it going to happen, 138 00:06:37,708 --> 00:06:39,337 how is it going to happen. 139 00:06:39,337 --> 00:06:41,548 Anticipation made them happy. 140 00:06:41,548 --> 00:06:45,417 This is, by the way, why people prefer Friday to Sunday. 141 00:06:45,417 --> 00:06:47,500 It's a really curious fact, 142 00:06:47,500 --> 00:06:50,917 because Friday is a day of work and Sunday is a day of pleasure, 143 00:06:50,917 --> 00:06:53,821 so you'd assume that people will prefer Sunday, 144 00:06:53,821 --> 00:06:55,542 but they don't. 145 00:06:55,542 --> 00:06:58,417 It's not because they really, really like being in the office 146 00:06:58,417 --> 00:07:00,384 and they can't stand strolling in the park 147 00:07:00,384 --> 00:07:02,045 or having a lazy brunch. 148 00:07:02,045 --> 00:07:04,181 We know that, because when you ask people 149 00:07:04,181 --> 00:07:06,885 about their ultimate favorite day of the week, 150 00:07:06,885 --> 00:07:09,705 surprise, surprise, Saturday comes in at first, 151 00:07:09,705 --> 00:07:12,625 then Friday, then Sunday. 152 00:07:12,625 --> 00:07:14,494 People prefer Friday 153 00:07:14,494 --> 00:07:18,458 because Friday brings with it the anticipation of the weekend ahead, 154 00:07:18,458 --> 00:07:20,375 all the plans that you have. 155 00:07:20,375 --> 00:07:23,079 On Sunday, the only thing you can look forward to 156 00:07:23,079 --> 00:07:25,333 is the work week. 157 00:07:25,333 --> 00:07:30,210 So optimists are people who expect more kisses in their future, 158 00:07:30,210 --> 00:07:32,131 more strolls in the park. 159 00:07:32,131 --> 00:07:36,038 And that anticipation enhances their wellbeing. 160 00:07:36,038 --> 00:07:39,002 In fact, without the optimism bias, 161 00:07:39,002 --> 00:07:41,752 we would all be slightly depressed. 162 00:07:41,752 --> 00:07:44,019 People with mild depression, 163 00:07:44,019 --> 00:07:46,998 they don't have a bias when they look into the future. 164 00:07:46,998 --> 00:07:51,220 They're actually more realistic than healthy individuals. 165 00:07:51,220 --> 00:07:53,321 But individuals with severe depression, 166 00:07:53,321 --> 00:07:55,150 they have a pessimistic bias. 167 00:07:55,150 --> 00:07:57,613 So they tend to expect the future 168 00:07:57,613 --> 00:08:00,090 to be worse than it ends up being. 169 00:08:00,090 --> 00:08:03,333 So optimism changes subjective reality. 170 00:08:03,333 --> 00:08:07,083 The way we expect the world to be changes the way we see it. 171 00:08:07,083 --> 00:08:10,325 But it also changes objective reality. 172 00:08:10,325 --> 00:08:13,052 It acts as a self-fulfilling prophecy. 173 00:08:13,052 --> 00:08:15,120 And that is the third reason 174 00:08:15,120 --> 00:08:18,300 why lowering your expectations will not make you happy. 175 00:08:18,300 --> 00:08:20,135 Controlled experiments have shown 176 00:08:20,135 --> 00:08:23,052 that optimism is not only related to success, 177 00:08:23,052 --> 00:08:24,859 it leads to success. 178 00:08:24,859 --> 00:08:29,729 Optimism leads to success in academia and sports and politics. 179 00:08:29,729 --> 00:08:34,204 And maybe the most surprising benefit of optimism is health. 180 00:08:34,204 --> 00:08:37,529 If we expect the future to be bright, 181 00:08:37,529 --> 00:08:40,269 stress and anxiety are reduced. 182 00:08:40,269 --> 00:08:44,489 So all in all, optimism has lots of benefits. 183 00:08:44,489 --> 00:08:47,500 But the question that was really confusing to me was, 184 00:08:47,500 --> 00:08:52,169 how do we maintain optimism in the face of reality? 185 00:08:52,169 --> 00:08:55,187 As an neuroscientist, this was especially confusing, 186 00:08:55,187 --> 00:08:58,083 because according to all the theories out there, 187 00:08:58,083 --> 00:09:02,271 when your expectations are not met, you should alter them. 188 00:09:02,271 --> 00:09:03,823 But this is not what we find. 189 00:09:03,823 --> 00:09:07,306 We asked people to come into our lab 190 00:09:07,306 --> 00:09:10,116 in order to try and figure out what was going on. 191 00:09:10,116 --> 00:09:12,663 We asked them to estimate their likelihood 192 00:09:12,663 --> 00:09:15,167 of experiencing different terrible events in their lives. 193 00:09:15,167 --> 00:09:19,542 So, for example, what is your likelihood of suffering from cancer? 194 00:09:19,542 --> 00:09:21,894 And then we told them the average likelihood 195 00:09:21,894 --> 00:09:24,875 of someone like them to suffer these misfortunes. 196 00:09:24,875 --> 00:09:28,440 So cancer, for example, is about 30 percent. 197 00:09:28,440 --> 00:09:31,375 And then we asked them again, 198 00:09:31,375 --> 00:09:34,250 "How likely are you to suffer from cancer?" 199 00:09:34,250 --> 00:09:36,498 What we wanted to know was 200 00:09:36,498 --> 00:09:39,167 whether people will take the information that we gave them 201 00:09:39,167 --> 00:09:41,298 to change their beliefs. 202 00:09:41,298 --> 00:09:43,667 And indeed they did -- 203 00:09:43,667 --> 00:09:46,248 but mostly when the information we gave them 204 00:09:46,248 --> 00:09:49,079 was better than what they expected. 205 00:09:49,079 --> 00:09:50,440 So for example, 206 00:09:50,440 --> 00:09:53,350 if someone said, "My likelihood of suffering from cancer 207 00:09:53,350 --> 00:09:55,731 is about 50 percent," 208 00:09:55,731 --> 00:09:58,252 and we said, "Hey, good news. 209 00:09:58,252 --> 00:10:00,833 The average likelihood is only 30 percent," 210 00:10:00,833 --> 00:10:02,879 the next time around they would say, 211 00:10:02,879 --> 00:10:05,594 "Well maybe my likelihood is about 35 percent." 212 00:10:05,594 --> 00:10:08,230 So they learned quickly and efficiently. 213 00:10:08,230 --> 00:10:10,780 But if someone started off saying, 214 00:10:10,780 --> 00:10:14,183 "My average likelihood of suffering from cancer is about 10 percent," 215 00:10:14,183 --> 00:10:16,875 and we said, "Hey, bad news. 216 00:10:16,875 --> 00:10:19,948 The average likelihood is about 30 percent," 217 00:10:19,948 --> 00:10:22,006 the next time around they would say, 218 00:10:22,006 --> 00:10:25,125 "Yep. Still think it's about 11 percent." 219 00:10:25,125 --> 00:10:26,815 (Laughter) 220 00:10:26,815 --> 00:10:30,134 So it's not that they didn't learn at all -- they did -- 221 00:10:30,134 --> 00:10:32,470 but much, much less than when we gave them 222 00:10:32,470 --> 00:10:34,943 positive information about the future. 223 00:10:34,943 --> 00:10:37,977 And it's not that they didn't remember the numbers that we gave them; 224 00:10:37,977 --> 00:10:41,050 everyone remembers that the average likelihood of cancer 225 00:10:41,050 --> 00:10:42,550 is about 30 percent 226 00:10:42,550 --> 00:10:45,329 and the average likelihood of divorce is about 40 percent. 227 00:10:45,329 --> 00:10:49,960 But they didn't think that those numbers were related to them. 228 00:10:49,960 --> 00:10:54,108 What this means is that warning signs such as these 229 00:10:54,108 --> 00:10:57,000 may only have limited impact. 230 00:10:57,000 --> 00:11:01,159 Yes, smoking kills, but mostly it kills the other guy. 231 00:11:01,159 --> 00:11:03,042 What I wanted to know was 232 00:11:03,042 --> 00:11:05,902 what was going on inside the human brain 233 00:11:05,902 --> 00:11:09,996 that prevented us from taking these warning signs personally. 234 00:11:09,996 --> 00:11:11,483 But at the same time, 235 00:11:11,483 --> 00:11:13,461 when we hear that the housing market is hopeful, 236 00:11:13,461 --> 00:11:17,577 we think, "Oh, my house is definitely going to double in price." 237 00:11:17,577 --> 00:11:19,662 To try and figure that out, 238 00:11:19,662 --> 00:11:22,135 I asked the participants in the experiment 239 00:11:22,135 --> 00:11:24,296 to lie in a brain imaging scanner. 240 00:11:24,296 --> 00:11:25,823 It looks like this. 241 00:11:25,823 --> 00:11:28,854 And using a method called functional MRI, 242 00:11:28,854 --> 00:11:32,460 we were able to identify regions in the brain 243 00:11:32,460 --> 00:11:35,277 that were responding to positive information. 244 00:11:35,277 --> 00:11:38,856 One of these regions is called the left inferior frontal gyrus. 245 00:11:38,856 --> 00:11:42,644 So if someone said, "My likelihood of suffering from cancer is 50 percent," 246 00:11:42,644 --> 00:11:44,500 and we said, "Hey, good news. 247 00:11:44,500 --> 00:11:46,790 Average likelihood is 30 percent," 248 00:11:46,790 --> 00:11:50,362 the left inferior frontal gyrus would respond fiercely. 249 00:11:50,362 --> 00:11:55,094 And it didn't matter if you're an extreme optimist, a mild optimist 250 00:11:55,094 --> 00:11:56,915 or slightly pessimistic, 251 00:11:56,915 --> 00:11:59,500 everyone's left inferior frontal gyrus 252 00:11:59,500 --> 00:12:01,344 was functioning perfectly well, 253 00:12:01,344 --> 00:12:04,250 whether you're Barack Obama or Woody Allen. 254 00:12:04,250 --> 00:12:05,894 On the other side of the brain, 255 00:12:05,894 --> 00:12:10,680 the right inferior frontal gyrus was responding to bad news. 256 00:12:10,680 --> 00:12:14,406 And here's the thing: it wasn't doing a very good job. 257 00:12:14,406 --> 00:12:16,421 The more optimistic you were, 258 00:12:16,421 --> 00:12:18,758 the less likely this region was 259 00:12:18,758 --> 00:12:21,740 to respond to unexpected negative information. 260 00:12:21,740 --> 00:12:24,798 And if your brain is failing 261 00:12:24,798 --> 00:12:28,023 at integrating bad news about the future, 262 00:12:28,023 --> 00:12:32,646 you will constantly leave your rose-tinted spectacles on. 263 00:12:32,646 --> 00:12:37,615 So we wanted to know, could we change this? 264 00:12:37,615 --> 00:12:41,058 Could we alter people's optimism bias 265 00:12:41,058 --> 00:12:44,990 by interfering with the brain activity in these regions? 266 00:12:44,990 --> 00:12:47,585 And there's a way for us to do that. 267 00:12:47,585 --> 00:12:50,212 This is my collaborator Ryota Kanai. 268 00:12:50,212 --> 00:12:54,167 And what he's doing is he's passing a small magnetic pulse 269 00:12:54,167 --> 00:12:56,286 through the skull of the participant in our study 270 00:12:56,286 --> 00:12:58,531 into their inferior frontal gyrus. 271 00:12:58,531 --> 00:13:00,458 And by doing that, 272 00:13:00,458 --> 00:13:03,362 he's interfering with the activity of this brain region 273 00:13:03,362 --> 00:13:04,577 for about half an hour. 274 00:13:04,577 --> 00:13:07,498 After that everything goes back to normal, I assure you. 275 00:13:07,498 --> 00:13:09,491 (Laughter) 276 00:13:09,491 --> 00:13:12,645 So let's see what happens. 277 00:13:12,645 --> 00:13:14,742 First of all, I'm going to show you 278 00:13:14,742 --> 00:13:17,446 the average amount of bias that we see. 279 00:13:17,446 --> 00:13:20,269 So if I was to test all of you now, 280 00:13:20,269 --> 00:13:22,063 this is the amount that you would learn 281 00:13:22,063 --> 00:13:25,183 more from good news relative to bad news. 282 00:13:25,183 --> 00:13:27,667 Now we interfere with the region 283 00:13:27,667 --> 00:13:32,134 that we found to integrate negative information in this task, 284 00:13:32,134 --> 00:13:35,698 and the optimism bias grew even larger. 285 00:13:35,698 --> 00:13:41,168 We made people more biased in the way that they process information. 286 00:13:41,168 --> 00:13:44,065 Then we interfered with the brain region 287 00:13:44,065 --> 00:13:47,583 that we found to integrate good news in this task, 288 00:13:47,583 --> 00:13:52,054 and the optimism bias disappeared. 289 00:13:52,054 --> 00:13:54,062 We were quite amazed by these results 290 00:13:54,062 --> 00:13:56,254 because we were able to eliminate 291 00:13:56,254 --> 00:13:59,450 a deep-rooted bias in humans. 292 00:13:59,450 --> 00:14:04,223 And at this point we stopped and we asked ourselves, 293 00:14:04,223 --> 00:14:09,325 would we want to shatter the optimism illusion into tiny little bits? 294 00:14:09,325 --> 00:14:14,369 If we could do that, would we want to take people's optimism bias away? 295 00:14:14,369 --> 00:14:18,969 Well I've already told you about all of the benefits of the optimism bias, 296 00:14:18,969 --> 00:14:23,290 which probably makes you want to hold onto it for dear life. 297 00:14:23,290 --> 00:14:25,375 But there are, of course, pitfalls, 298 00:14:25,375 --> 00:14:28,495 and it would be really foolish of us to ignore them. 299 00:14:28,495 --> 00:14:32,041 Take for example this email I recieved 300 00:14:32,041 --> 00:14:34,735 from a firefighter here in California. 301 00:14:34,735 --> 00:14:38,039 He says, "Fatality investigations for firefighters 302 00:14:38,039 --> 00:14:42,181 often include 'We didn't think the fire was going to do that,' 303 00:14:42,181 --> 00:14:44,483 even when all of the available information 304 00:14:44,483 --> 00:14:46,738 was there to make safe decisions." 305 00:14:46,738 --> 00:14:50,612 This captain is going to use our findings on the optimism bias 306 00:14:50,612 --> 00:14:52,804 to try to explain to the firefighters 307 00:14:52,804 --> 00:14:55,013 why they think the way they do, 308 00:14:55,013 --> 00:15:02,139 to make them acutely aware of this very optimistic bias in humans. 309 00:15:02,139 --> 00:15:07,258 So unrealistic optimism can lead to risky behavior, 310 00:15:07,258 --> 00:15:10,896 to financial collapse, to faulty planning. 311 00:15:10,896 --> 00:15:13,034 The British government, for example, 312 00:15:13,034 --> 00:15:15,708 has acknowledged that the optimism bias 313 00:15:15,708 --> 00:15:18,995 can make individuals more likely 314 00:15:18,995 --> 00:15:23,021 to underestimate the costs and durations of projects. 315 00:15:23,021 --> 00:15:27,275 So they have adjusted the 2012 Olympic budget 316 00:15:27,275 --> 00:15:29,386 for the optimism bias. 317 00:15:29,386 --> 00:15:31,573 My friend who's getting married in a few weeks 318 00:15:31,573 --> 00:15:34,007 has done the same for his wedding budget. 319 00:15:34,007 --> 00:15:37,069 And by the way, when I asked him about his own likelihood of divorce, 320 00:15:37,069 --> 00:15:40,629 he said he was quite sure it was zero percent. 321 00:15:40,629 --> 00:15:43,046 So what we would really like to do, 322 00:15:43,046 --> 00:15:47,207 is we would like to protect ourselves from the dangers of optimism, 323 00:15:47,207 --> 00:15:50,435 but at the same time remain hopeful, 324 00:15:50,435 --> 00:15:53,279 benefiting from the many fruits of optimism. 325 00:15:53,279 --> 00:15:56,083 And I believe there's a way for us to do that. 326 00:15:56,083 --> 00:15:58,143 The key here really is knowledge. 327 00:15:58,143 --> 00:16:01,454 We're not born with an innate understanding of our biases. 328 00:16:01,454 --> 00:16:05,295 These have to be identified by scientific investigation. 329 00:16:05,295 --> 00:16:09,479 But the good news is that becoming aware of the optimism bias 330 00:16:09,479 --> 00:16:11,254 does not shatter the illusion. 331 00:16:11,254 --> 00:16:12,802 It's like visual illusions, 332 00:16:12,802 --> 00:16:16,292 in which understanding them does not make them go away. 333 00:16:16,292 --> 00:16:18,529 And this is good because it means 334 00:16:18,529 --> 00:16:21,002 we should be able to strike a balance, 335 00:16:21,002 --> 00:16:23,429 to come up with plans and rules 336 00:16:23,429 --> 00:16:26,212 to protect ourselves from unrealistic optimism, 337 00:16:26,212 --> 00:16:29,364 but at the same time remain hopeful. 338 00:16:29,364 --> 00:16:32,788 I think this cartoon portrays it nicely. 339 00:16:32,788 --> 00:16:36,314 Because if you're one of these pessimistic penguins up there 340 00:16:36,314 --> 00:16:38,433 who just does not believe they can fly, 341 00:16:38,433 --> 00:16:40,792 you certainly never will. 342 00:16:40,792 --> 00:16:42,623 Because to make any kind of progress, 343 00:16:42,623 --> 00:16:44,973 we need to be able to imagine a different reality, 344 00:16:44,973 --> 00:16:48,704 and then we need to believe that that reality is possible. 345 00:16:48,714 --> 00:16:52,238 But if you are an extreme optimistic penguin 346 00:16:52,238 --> 00:16:55,000 who just jumps down blindly hoping for the best, 347 00:16:55,000 --> 00:16:59,781 you might find yourself in a bit of a mess when you hit the ground. 348 00:16:59,781 --> 00:17:01,670 But if you're an optimistic penguin 349 00:17:01,670 --> 00:17:03,466 who believes they can fly, 350 00:17:03,466 --> 00:17:06,129 but then adjusts a parachute to your back 351 00:17:06,129 --> 00:17:09,146 just in case things don't work out exactly as you had planned, 352 00:17:09,146 --> 00:17:11,009 you will soar like an eagle, 353 00:17:11,009 --> 00:17:14,058 even if you're just a penguin. 354 00:17:14,058 --> 00:17:15,820 Thank you. 355 00:17:15,820 --> 00:17:18,756 (Applause)