1 00:00:00,917 --> 00:00:01,792 I'm going to talk to you about optimism -- 2 00:00:01,792 --> 00:00:05,321 or more precisely, the optimism bias. 3 00:00:05,321 --> 00:00:06,750 It's a cognitive illusion 4 00:00:06,750 --> 00:00:10,000 that we've been studying in my lab for the past few years, 5 00:00:10,000 --> 00:00:11,750 and 80 percent of us have it. 6 00:00:11,750 --> 00:00:13,100 It's our tendency to overestimate 7 00:00:13,100 --> 00:00:17,792 our likelihood of experiencing good events in our lives 8 00:00:17,792 --> 00:00:19,792 and underestimate our likelihood of experiencing bad events. 9 00:00:19,792 --> 00:00:24,917 So we underestimate our likelihood of suffering from cancer, 10 00:00:24,917 --> 00:00:25,792 being in a car accident. 11 00:00:25,792 --> 00:00:28,917 We overestimate our longevity, our career prospects. 12 00:00:28,917 --> 00:00:32,500 In short, we're more optimistic than realistic, 13 00:00:32,500 --> 00:00:34,708 but we are oblivious to the fact. 14 00:00:34,708 --> 00:00:36,458 Take marriage for example. 15 00:00:36,458 --> 00:00:40,500 In the Western World, divorce rates are about 40 percent. 16 00:00:40,500 --> 00:00:44,000 That means that out of five married couples, 17 00:00:44,000 --> 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 --> 00:00:53,542 they estimate it at zero percent. 20 00:00:53,542 --> 00:00:56,625 And even divorce lawyers, who should really know better, 21 00:00:56,625 --> 00:01:00,750 hugely underestimate their own likelihood of divorce. 22 00:01:00,750 --> 00:01:04,000 So it turns out that optimists are not less likely to divorce, 23 00:01:04,000 --> 00:01:07,083 but they are more likely to remarry. 24 00:01:07,083 --> 00:01:08,833 In the words of Samuel Johnson, 25 00:01:08,833 --> 00:01:13,583 "Remarriage is the triumph of hope over experience." 26 00:01:13,583 --> 00:01:14,792 (Laughter) 27 00:01:14,792 --> 00:01:19,750 So if we're married, we're more likely to have kids. 28 00:01:19,750 --> 00:01:23,000 And we all think our kids will be especially talented. 29 00:01:23,000 --> 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 --> 00:01:30,667 that he's a really bad example of the optimism bias, 32 00:01:30,667 --> 00:01:34,125 because he is in fact uniquely talented. 33 00:01:34,125 --> 00:01:35,083 (Laughter) 34 00:01:35,083 --> 00:01:37,167 And I'm not alone. 35 00:01:37,167 --> 00:01:38,042 Out of four British people, three said 36 00:01:38,042 --> 00:01:42,750 that they were optimistic about the future of their own families. 37 00:01:42,750 --> 00:01:44,917 That's 75 percent. 38 00:01:44,917 --> 00:01:46,667 But only 30 percent said 39 00:01:46,667 --> 00:01:49,750 that they thought families in general 40 00:01:49,750 --> 00:01:51,500 are doing better than a few generations ago. 41 00:01:51,500 --> 00:01:53,583 And this is a really important point, 42 00:01:53,583 --> 00:01:55,333 because we're optimistic about ourselves, 43 00:01:55,333 --> 00:01:57,412 we're optimistic about our kids, 44 00:01:57,412 --> 00:02:00,216 we're optimistic about our families, 45 00:02:00,216 --> 00:02:02,783 but we're not so optimistic about the guy sitting next to us, 46 00:02:02,783 --> 00:02:04,458 and we're somewhat pessimistic 47 00:02:04,458 --> 00:02:08,583 about the fate of our fellow citizens and the fate of our country. 48 00:02:08,583 --> 00:02:12,542 But private optimism about our own personal future 49 00:02:12,542 --> 00:02:14,292 remains persistent. 50 00:02:14,292 --> 00:02:18,250 And it doesn't mean that we think things will magically turn out okay, 51 00:02:18,250 --> 00:02:22,375 but rather that we have the unique ability to make it so. 52 00:02:22,375 --> 00:02:25,292 Now I'm a scientist, I do experiments. 53 00:02:25,292 --> 00:02:26,167 So to show you what I mean, 54 00:02:26,167 --> 00:02:29,625 I'm going to do an experiment here with you. 55 00:02:29,625 --> 00:02:33,875 So I'm going to give you a list of abilities and characteristics, 56 00:02:33,875 --> 00:02:37,292 and I want you to think for each of these abilities 57 00:02:37,292 --> 00:02:40,500 where you stand relative to the rest of the population. 58 00:02:40,500 --> 00:02:44,917 The first one is getting along well with others. 59 00:02:44,917 --> 00:02:48,708 Who here believes they're at the bottom 25 percent? 60 00:02:48,708 --> 00:02:52,583 Okay, that's about 10 people out of 1,500. 61 00:02:52,583 --> 00:02:58,458 Who believes they're at the top 25 percent? 62 00:02:58,458 --> 00:03:01,583 That's most of us here. 63 00:03:01,583 --> 00:03:05,375 Okay, now do the same for your driving ability. 64 00:03:05,375 --> 00:03:08,958 How interesting are you? 65 00:03:08,958 --> 00:03:10,971 How attractive are you? 66 00:03:10,971 --> 00:03:14,833 How honest are you? 67 00:03:14,833 --> 00:03:18,417 And finally, how modest are you? 68 00:03:18,417 --> 00:03:23,167 So most of us put ourselves above average 69 00:03:23,167 --> 00:03:24,042 on most of these abilities. 70 00:03:24,042 --> 00:03:27,327 Now this is statistically impossible. 71 00:03:27,327 --> 00:03:29,248 We can't all be better than everyone else. 72 00:03:29,248 --> 00:03:31,583 (Laughter) 73 00:03:31,583 --> 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 --> 00:03:39,833 Because we're more social, more interesting. 76 00:03:39,833 --> 00:03:43,042 And it's a global phenomenon. 77 00:03:43,042 --> 00:03:44,833 The optimism bias has been observed 78 00:03:44,833 --> 00:03:46,583 in many different countries -- 79 00:03:46,583 --> 00:03:50,333 in Western cultures, in non-Western cultures, 80 00:03:50,333 --> 00:03:51,208 in females and males, 81 00:03:51,208 --> 00:03:53,625 in kids, in the elderly. 82 00:03:53,625 --> 00:03:54,500 It's quite widespread. 83 00:03:54,500 --> 00:03:56,250 But the question is, Is it good for us? 84 00:03:56,250 --> 00:04:01,208 So some people say no. 85 00:04:01,208 --> 00:04:03,833 Some people say the secret to happiness 86 00:04:03,833 --> 00:04:06,833 is low expectations. 87 00:04:06,833 --> 00:04:08,583 I think the logic goes something like this: 88 00:04:08,583 --> 00:04:10,333 If we don't expect greatness, 89 00:04:10,333 --> 00:04:15,167 if we don't expect to find love and be healthy and successful, 90 00:04:15,167 --> 00:04:18,250 well we're not going to be disappointed when these things don't happen. 91 00:04:18,250 --> 00:04:21,750 And if we're not disappointed when good things don't happen, 92 00:04:21,750 --> 00:04:23,375 and we're pleasantly surprised when they do, 93 00:04:23,375 --> 00:04:25,125 we will be happy. 94 00:04:25,125 --> 00:04:27,858 So it's a very good theory, 95 00:04:27,858 --> 00:04:30,208 but it turns out to be wrong for three reasons. 96 00:04:30,208 --> 00:04:35,500 Number one: Whatever happens, whether you succeed or you fail, 97 00:04:35,500 --> 00:04:37,250 people with high expectations always feel better. 98 00:04:37,250 --> 00:04:42,875 Because how we feel when we get dumped or win employee of the month 99 00:04:42,875 --> 00:04:45,458 depends on how we interpret that event. 100 00:04:45,458 --> 00:04:49,708 The psychologists Margaret Marshall and John Brown 101 00:04:49,708 --> 00:04:52,333 studied students with high and low expectations. 102 00:04:52,333 --> 00:04:55,625 And they found that when people with high expectations succeed, 103 00:04:55,625 --> 00:04:59,750 they attribute that success to their own traits. 104 00:04:59,750 --> 00:05:01,500 "I'm a genius, therefore I got an A, 105 00:05:01,500 --> 00:05:04,667 therefore I'll get an A again and again in the future." 106 00:05:04,667 --> 00:05:07,625 When they failed, it wasn't because they were dumb, 107 00:05:07,625 --> 00:05:10,875 but because the exam just happened to be unfair. 108 00:05:10,875 --> 00:05:12,958 Next time they will do better. 109 00:05:12,958 --> 00:05:16,250 People with low expectations do the opposite. 110 00:05:16,250 --> 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 --> 00:05:23,792 it was because the exam just happened to be really easy. 113 00:05:23,792 --> 00:05:26,500 Next time reality would catch up with them. 114 00:05:26,500 --> 00:05:28,958 So they felt worse. 115 00:05:28,958 --> 00:05:31,583 Number two: Regardless of the outcome, 116 00:05:31,583 --> 00:05:35,583 the pure act of anticipation makes us happy. 117 00:05:35,583 --> 00:05:38,667 The behavioral economist George Lowenstein 118 00:05:38,667 --> 00:05:40,417 asked students in his university 119 00:05:40,417 --> 00:05:43,625 to imagine getting a passionate kiss from a celebrity, any celebrity. 120 00:05:43,625 --> 00:05:47,125 Then he said, "How much are you willing to pay 121 00:05:47,125 --> 00:05:50,375 to get a kiss from a celebrity 122 00:05:50,375 --> 00:05:52,125 if the kiss was delivered immediately, 123 00:05:52,125 --> 00:05:57,625 in three hours, in 24 hours, in three days, 124 00:05:57,625 --> 00:05:59,458 in one year, in 10 years? 125 00:05:59,458 --> 00:06:01,542 He found that the students were willing to pay the most 126 00:06:01,542 --> 00:06:04,833 not to get a kiss immediately, 127 00:06:04,833 --> 00:06:08,167 but to get a kiss in three days. 128 00:06:08,167 --> 00:06:10,583 They were willing to pay extra in order to wait. 129 00:06:10,583 --> 00:06:14,417 Now they weren't willing to wait a year or 10 years; 130 00:06:14,417 --> 00:06:16,500 no one wants an aging celebrity. 131 00:06:16,500 --> 00:06:21,042 But three days seemed to be the optimum amount. 132 00:06:21,042 --> 00:06:22,792 So why is that? 133 00:06:22,792 --> 00:06:26,708 Well if you get the kiss now, it's over an done with. 134 00:06:26,708 --> 00:06:28,458 But if you get the kiss in three days, 135 00:06:28,458 --> 00:06:33,458 well that's three days of jittery anticipation, the thrill of the wait. 136 00:06:33,458 --> 00:06:34,958 The students wanted that time 137 00:06:34,958 --> 00:06:37,708 to imagine where is it going to happen, 138 00:06:37,708 --> 00:06:38,583 how is it going to happen. 139 00:06:38,583 --> 00:06:40,333 Anticipation made them happy. 140 00:06:40,333 --> 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 --> 00:06:53,083 so you'd assume that people will prefer Sunday, 144 00:06:53,083 --> 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 --> 00:06:59,292 and they can't stand strolling in the park 147 00:06:59,292 --> 00:07:01,583 or having a lazy brunch. 148 00:07:01,583 --> 00:07:02,458 We know that, because when you ask people 149 00:07:02,458 --> 00:07:04,208 about their ultimate favorite day of the week, 150 00:07:04,208 --> 00:07:08,167 surprise, surprise, Saturday comes in at first, 151 00:07:08,167 --> 00:07:12,333 then Friday, then Sunday. 152 00:07:12,333 --> 00:07:13,417 People prefer Friday 153 00:07:13,417 --> 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 --> 00:07:22,125 On Sunday, the only thing you can look forward to 156 00:07:22,125 --> 00:07:23,000 is the work week. 157 00:07:23,000 --> 00:07:29,625 So optimists are people who expect more kisses in their future, 158 00:07:29,625 --> 00:07:30,500 more strolls in the park. 159 00:07:30,500 --> 00:07:35,500 And that anticipation enhances their wellbeing. 160 00:07:35,500 --> 00:07:38,125 In fact, without the optimism bias, 161 00:07:38,125 --> 00:07:40,875 we would all slightly depressed. 162 00:07:40,875 --> 00:07:43,250 People with mild depression, 163 00:07:43,250 --> 00:07:45,875 they don't have a bias when they look into the future. 164 00:07:45,875 --> 00:07:49,958 They're actually more realistic than healthy individuals. 165 00:07:49,958 --> 00:07:53,167 But individuals with severe depression, 166 00:07:53,167 --> 00:07:54,042 they have a pessimistic bias. 167 00:07:54,042 --> 00:07:56,875 So they tend to expect the future 168 00:07:56,875 --> 00:07:59,167 to be worse than it ends up being. 169 00:07:59,167 --> 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 --> 00:08:08,833 But it also changes objective reality. 172 00:08:08,833 --> 00:08:12,083 It acts as a self-fulfilling prophecy. 173 00:08:12,083 --> 00:08:15,458 And that is the third reason 174 00:08:15,458 --> 00:08:17,208 why lowering your expectations will not make you happy. 175 00:08:17,208 --> 00:08:19,750 Controlled experiments have shown 176 00:08:19,750 --> 00:08:22,667 that optimism is not only related to success, 177 00:08:22,667 --> 00:08:23,542 it leads to success. 178 00:08:23,542 --> 00:08:28,667 Optimism leads to success in academia and sports and politics. 179 00:08:28,667 --> 00:08:32,958 And maybe the most surprising benefit of optimism is health. 180 00:08:32,958 --> 00:08:37,083 If we expect the future to be bright, 181 00:08:37,083 --> 00:08:39,500 stress and anxiety are reduced. 182 00:08:39,500 --> 00:08:43,458 So all in all, optimism has lots of benefits. 183 00:08:43,458 --> 00:08:47,500 But the question that was really confusing to me was, 184 00:08:47,500 --> 00:08:51,000 How do we maintain optimism in the face of reality? 185 00:08:51,000 --> 00:08:54,833 As an neuroscientist, this was especially confusing, 186 00:08:54,833 --> 00:08:58,083 because according to all the theories out there, 187 00:08:58,083 --> 00:09:02,625 when your expectations are not met, you should alter them. 188 00:09:02,625 --> 00:09:03,500 But this is not what we find. 189 00:09:03,500 --> 00:09:06,583 We asked people to come into our lab 190 00:09:06,583 --> 00:09:09,208 in order to try and figure out what was going on. 191 00:09:09,208 --> 00:09:12,417 We asked them to estimate their likelihood 192 00:09:12,417 --> 00:09:14,167 of experiencing different terrible events in their lives. 193 00:09:14,167 --> 00:09:19,542 So for example, what is your likelihood of suffering from cancer? 194 00:09:19,542 --> 00:09:20,417 And then we told them the average likelihood 195 00:09:20,417 --> 00:09:24,875 of someone like them to suffer these misfortunes. 196 00:09:24,875 --> 00:09:26,625 So cancer, for example, is about 30 percent. 197 00:09:26,625 --> 00:09:31,375 And then we asked them again, 198 00:09:31,375 --> 00:09:32,250 How likely are you to suffer from cancer? 199 00:09:32,250 --> 00:09:35,667 What we wanted to know 200 00:09:35,667 --> 00:09:39,167 was whether people will take the information that we gave them 201 00:09:39,167 --> 00:09:40,667 to change their beliefs. 202 00:09:40,667 --> 00:09:43,667 And indeed they did -- 203 00:09:43,667 --> 00:09:45,417 but mostly when the information we gave them 204 00:09:45,417 --> 00:09:48,417 was better that what they expected. 205 00:09:48,417 --> 00:09:49,292 So for example, 206 00:09:49,292 --> 00:09:52,458 if someone said, "My likelihood of suffering from cancer 207 00:09:52,458 --> 00:09:54,208 is about 50 percent," 208 00:09:54,208 --> 00:09:57,667 and we said, "Hey, good news. 209 00:09:57,667 --> 00:10:00,833 The average likelihood is only 30 percent," 210 00:10:00,833 --> 00:10:02,125 the next time around they would say, 211 00:10:02,125 --> 00:10:04,917 "Well maybe my likelihood is about 35 percent." 212 00:10:04,917 --> 00:10:07,292 So they learned quickly and efficiently. 213 00:10:07,292 --> 00:10:09,042 But if someone started off saying, 214 00:10:09,042 --> 00:10:12,583 "My average likelihood of suffering from cancer is about 10 percent," 215 00:10:12,583 --> 00:10:16,875 and we said, "Hey, bad news. 216 00:10:16,875 --> 00:10:19,333 The average likelihood is about 30 percent," 217 00:10:19,333 --> 00:10:21,083 they next time around they would say, 218 00:10:21,083 --> 00:10:25,125 "Yep. Still think it's about 11 percent." 219 00:10:25,125 --> 00:10:26,000 (Laughter) 220 00:10:26,000 --> 00:10:28,042 So it's not that they didn't learn at all -- they did -- 221 00:10:28,042 --> 00:10:32,208 but much, much less than when we gave them 222 00:10:32,208 --> 00:10:33,958 positive information about the future. 223 00:10:33,958 --> 00:10:37,208 And it's not that they didn't remember the numbers that we gave them; 224 00:10:37,208 --> 00:10:39,958 everyone remembers that the average likelihood of cancer 225 00:10:39,958 --> 00:10:40,833 is about 30 percent 226 00:10:40,833 --> 00:10:44,083 and the average likelihood of divorce is about 40 percent. 227 00:10:44,083 --> 00:10:48,375 But they didn't think that those numbers were related to them. 228 00:10:48,375 --> 00:10:51,000 What this means is that warning signs such as these 229 00:10:51,000 --> 00:10:55,292 may only have limited impact. 230 00:10:55,292 --> 00:10:58,667 Yes, smoking kills, but mostly it kills the other guy. 231 00:10:58,667 --> 00:11:03,042 What I wanted to know 232 00:11:03,042 --> 00:11:05,333 was what was going on inside the human brain 233 00:11:05,333 --> 00:11:09,458 that prevented us from taking these warning signs personally. 234 00:11:09,458 --> 00:11:12,375 But at the same time, when we hear that the housing market is hopeful, 235 00:11:12,375 --> 00:11:16,500 we think, "Oh, my house is definitely going to double in price." 236 00:11:16,500 --> 00:11:19,000 To try and figure that out, 237 00:11:19,000 --> 00:11:20,750 I asked the participants in the experiment 238 00:11:20,750 --> 00:11:23,958 to lie in a brain imaging scanner. 239 00:11:23,958 --> 00:11:25,208 It looks like this. 240 00:11:25,208 --> 00:11:27,792 And using a method called functional MRI, 241 00:11:27,792 --> 00:11:31,583 we were able to identify regions in the brain 242 00:11:31,583 --> 00:11:35,000 that were responding to positive information. 243 00:11:35,000 --> 00:11:37,625 One of these regions is called the left inferior frontal gyrus. 244 00:11:37,625 --> 00:11:41,875 So if someone said, "My likelihood of suffering from cancer is 50 percent," 245 00:11:41,875 --> 00:11:44,500 and we said, "Hey, good news. 246 00:11:44,500 --> 00:11:45,375 Average likelihood is 30 percent," 247 00:11:45,375 --> 00:11:49,500 the left inferior frontal gyrus would respond fiercely. 248 00:11:49,500 --> 00:11:52,125 And it didn't matter if you're an extreme optimist, a mild optimist 249 00:11:52,125 --> 00:11:54,500 or slightly pessimistic, 250 00:11:54,500 --> 00:11:59,500 everyone's left inferior frontal gyrus 251 00:11:59,500 --> 00:12:00,375 was functioning perfectly well, 252 00:12:00,375 --> 00:12:04,250 whether you're Barack Obama or Woody Allen. 253 00:12:04,250 --> 00:12:05,125 On the other side of the brain, 254 00:12:05,125 --> 00:12:09,542 the right inferior frontal gyrus was responding to bad news. 255 00:12:09,542 --> 00:12:14,083 And here's the thing, it wasn't doing a very good job. 256 00:12:14,083 --> 00:12:16,083 The more optimistic you were, 257 00:12:16,083 --> 00:12:16,958 the less likely this region was 258 00:12:16,958 --> 00:12:21,125 to respond to unexpected negative information. 259 00:12:21,125 --> 00:12:22,875 And if your brain is failing 260 00:12:22,875 --> 00:12:27,500 at integrating bad news about the future, 261 00:12:27,500 --> 00:12:32,000 you will constantly leave your rose-tinted spectacles on. 262 00:12:32,000 --> 00:12:36,000 So we wanted to know could we change this. 263 00:12:36,000 --> 00:12:40,458 Could we alter people's optimism bias 264 00:12:40,458 --> 00:12:44,375 by interfering with the brain activity in these regions? 265 00:12:44,375 --> 00:12:47,000 And there's a way for us to do that. 266 00:12:47,000 --> 00:12:48,750 This is my collaborator Ryota Kanai. 267 00:12:48,750 --> 00:12:54,167 And what he's doing is he's passing a small magnetic pulse 268 00:12:54,167 --> 00:12:55,917 through the skull of the participant in our study 269 00:12:55,917 --> 00:12:58,208 into their inferior frontal gyrus. 270 00:12:58,208 --> 00:13:00,458 And my doing that, 271 00:13:00,458 --> 00:13:02,208 he's interfering with the activity of this brain region 272 00:13:02,208 --> 00:13:05,208 for about half an hour. 273 00:13:05,208 --> 00:13:06,083 After that everything goes back to normal, I assure you. 274 00:13:06,083 --> 00:13:07,833 (Laughter) 275 00:13:07,833 --> 00:13:09,583 So let's see what happens. 276 00:13:09,583 --> 00:13:14,542 First of all, I'm going to show you 277 00:13:14,542 --> 00:13:16,292 the average amount of bias that we see. 278 00:13:16,292 --> 00:13:19,792 So if I was to test all of you now, 279 00:13:19,792 --> 00:13:22,125 this is the amount that you would learn 280 00:13:22,125 --> 00:13:23,875 more from good news relative to bad news. 281 00:13:23,875 --> 00:13:27,667 Now we interfere with the region 282 00:13:27,667 --> 00:13:31,042 that we found to integrate negative information in this task, 283 00:13:31,042 --> 00:13:34,083 and the optimism bias grew even larger. 284 00:13:34,083 --> 00:13:40,583 We made people more biased in the way that they process information. 285 00:13:40,583 --> 00:13:43,542 Then we interfered with the brain region 286 00:13:43,542 --> 00:13:47,583 that we found to integrate good news in this task, 287 00:13:47,583 --> 00:13:50,208 and the optimism bias disappeared. 288 00:13:50,208 --> 00:13:54,000 We were quite amazed by these results 289 00:13:54,000 --> 00:13:55,792 because we were able to eliminate 290 00:13:55,792 --> 00:13:57,542 a deep-rooted bias in humans. 291 00:13:57,542 --> 00:14:02,500 And at this point we stopped and we asked ourselves, 292 00:14:02,500 --> 00:14:08,125 Would we want to shatter the optimism illusion into tiny little bits? 293 00:14:08,125 --> 00:14:13,292 If we could do that, would we want to take people's optimism bias away? 294 00:14:13,292 --> 00:14:18,292 Well I've already told you about all of the benefits of the optimism bias, 295 00:14:18,292 --> 00:14:22,875 which probably makes you want hold onto it for dear life. 296 00:14:22,875 --> 00:14:23,750 But there are, of course, pitfalls, 297 00:14:23,750 --> 00:14:27,833 and it would be really foolish of us to ignore them. 298 00:14:27,833 --> 00:14:31,333 Take for example this email I recieved 299 00:14:31,333 --> 00:14:33,750 from a firefighter here in California. 300 00:14:33,750 --> 00:14:37,208 He says, "Fatality investigations for firefighters 301 00:14:37,208 --> 00:14:40,458 often include 'we didn't think the fire was going to do that' 302 00:14:40,458 --> 00:14:43,083 even when all of the available information 303 00:14:43,083 --> 00:14:46,292 was there to make safe decisions." 304 00:14:46,292 --> 00:14:49,750 This captain is going to use our findings on the optimism bias 305 00:14:49,750 --> 00:14:50,625 to try and explain to the firefighters 306 00:14:50,625 --> 00:14:53,875 why they think the way they do, 307 00:14:53,875 --> 00:14:59,708 to make them acutely aware of this very optimistic bias in humans. 308 00:14:59,708 --> 00:15:05,750 So unrealistic optimism can lead to risky behavior, 309 00:15:05,750 --> 00:15:09,250 to financial collapse, to faulty planning. 310 00:15:09,250 --> 00:15:11,542 The British government, for example, 311 00:15:11,542 --> 00:15:15,708 has a acknowledged that the optimism bias 312 00:15:15,708 --> 00:15:18,333 can make individuals more likely 313 00:15:18,333 --> 00:15:22,375 to underestimate the costs and durations of projects. 314 00:15:22,375 --> 00:15:25,875 So they have adjusted the 2012 Olympic budget for the optimism bias. 315 00:15:25,875 --> 00:15:29,958 My friend who's getting married in a few weeks 316 00:15:29,958 --> 00:15:32,792 has done the same for his wedding budget. 317 00:15:32,792 --> 00:15:35,792 And by the way, when I asked him about his own likelihood of divorce, 318 00:15:35,792 --> 00:15:39,875 he said he was quite sure it was zero percent. 319 00:15:39,875 --> 00:15:42,292 So what we would really like to do, 320 00:15:42,292 --> 00:15:45,792 is we would like to protect ourselves from the dangers of optimism, 321 00:15:45,792 --> 00:15:50,958 but at the same time remain hopeful, 322 00:15:50,958 --> 00:15:51,833 benefiting from the many fruits of optimism. 323 00:15:51,833 --> 00:15:56,083 And I believe there's a way for us to do that. 324 00:15:56,083 --> 00:15:56,958 The key here really is knowledge. 325 00:15:56,958 --> 00:16:00,208 We're not born with an innate understanding of our biases. 326 00:16:00,208 --> 00:16:02,833 These have to be identified by scientific investigation. 327 00:16:02,833 --> 00:16:07,833 But the good news is that becoming aware of the optimism bias 328 00:16:07,833 --> 00:16:10,208 does not shatter the illusion. 329 00:16:10,208 --> 00:16:12,125 It's like visual illusions 330 00:16:12,125 --> 00:16:16,292 in which understanding them does not make them go away. 331 00:16:16,292 --> 00:16:20,083 And this is good because it means we should be able to strike a balance, 332 00:16:20,083 --> 00:16:23,583 to come up with plans and rules 333 00:16:23,583 --> 00:16:24,458 to protect ourselves from unrealistic optimism, 334 00:16:24,458 --> 00:16:28,625 but at the same time remain hopeful. 335 00:16:28,625 --> 00:16:31,250 I think this cartoon portrays it nicely. 336 00:16:31,250 --> 00:16:36,083 Because if you're one of these pessimistic penguins up there 337 00:16:36,083 --> 00:16:37,833 who just does not believe they can fly, 338 00:16:37,833 --> 00:16:40,792 you certainly never will. 339 00:16:40,792 --> 00:16:41,792 Because to make any kind of progress, 340 00:16:41,792 --> 00:16:43,542 we need to be able to imagine a different reality, 341 00:16:43,542 --> 00:16:45,958 and then we need to believe that that reality is possible. 342 00:16:48,729 --> 00:16:51,500 But if you are an extreme optimistic penguin 343 00:16:51,500 --> 00:16:55,000 who just jumps down blindly hoping for the best, 344 00:16:55,000 --> 00:16:58,458 you might find yourself in a bit of a mess when you hit the ground. 345 00:16:58,458 --> 00:17:00,208 But if you're an optimistic penguin 346 00:17:00,208 --> 00:17:05,958 who believes they can fly, but adjusts a parachute to your back 347 00:17:05,958 --> 00:17:08,208 just in case things don't work out exactly as you had planned, 348 00:17:08,208 --> 00:17:09,917 you will soar like an eagle, 349 00:17:09,917 --> 00:17:13,458 even if you're just a penguin. 350 00:17:13,458 --> 00:17:14,333 Thank you. 351 00:17:14,333 --> 00:17:17,833 (Applause)