1 00:00:33,570 --> 00:00:39,930 The world is a fascinating place, filled with natural wonders and manmade marvels. 2 00:00:39,930 --> 00:00:42,860 It challenges us to want to learn all about it. 3 00:00:42,860 --> 00:00:44,450 How do things work? 4 00:00:44,450 --> 00:00:46,980 What's the answer to this old mystery? 5 00:00:46,980 --> 00:00:51,000 Is this new thing good for me or bad for me? 6 00:00:51,000 --> 00:00:53,760 But there's a lot of pseudoscience out there. 7 00:00:53,760 --> 00:00:57,520 Marketers make dubious claims to sell us their products. 8 00:00:57,520 --> 00:00:59,860 People believe weird things. 9 00:00:59,860 --> 00:01:05,960 TV documentaries blur the line between fact and fiction in the name of entertainment. 10 00:01:05,960 --> 00:01:12,460 And in the midst of all this, we're all making life decisions based on questionable knowledge. 11 00:01:12,470 --> 00:01:17,619 How do we learn to separate what's real from what's not; what works from what doesn't; 12 00:01:17,619 --> 00:01:20,600 the dependable from the fallible? 13 00:01:20,600 --> 00:01:25,880 How do we keep our curiosity from leading us to the wrong conclusion? 14 00:01:25,880 --> 00:01:31,560 It can be done, and this is your guide. 15 00:01:44,700 --> 00:01:45,960 I'm Brian Dunning. 16 00:01:45,970 --> 00:01:50,759 I'm a science writer, and I've spent the last 10 years writing and podcasting about urban 17 00:01:50,760 --> 00:01:57,970 legends, paranormal phenomena, ancient mysteries, and the world's biggest science discoveries, 18 00:01:57,980 --> 00:02:02,180 sharing what I've learned about what's real and what's not. 19 00:02:02,180 --> 00:02:06,980 One thing I can say for sure is that we're all curious about this kind of stuff, 20 00:02:06,980 --> 00:02:12,380 and the more amazing something is, the more we want it to be true. 21 00:02:12,380 --> 00:02:15,180 Right now I’m in Death Valley, California. 22 00:02:15,180 --> 00:02:19,140 I'm on my way to see a surprising phenomenon that I learned about in college; 23 00:02:19,140 --> 00:02:22,750 a mystery that nobody had ever solved. 24 00:02:22,750 --> 00:02:29,040 It was so astonishing to me that it changed the course of my life, and led me to become a science writer. 25 00:02:29,040 --> 00:02:31,360 We'll be there pretty soon. 26 00:02:31,360 --> 00:02:35,820 Lots of us get captivated by provocative stories, just like I did. 27 00:02:35,820 --> 00:02:43,280 The other day I sat down with some friends to see what kinds of things they'd heard that really intrigued them. 28 00:02:43,280 --> 00:02:46,660 I'm here with my friends Tamara, Heather, and Dan, 29 00:02:46,660 --> 00:02:51,020 and we're talking about things we've seen on TV that seem amazing or surprising. 30 00:02:51,020 --> 00:02:54,760 Yeah, you know I watch these documentaries on TV about different subjects, 31 00:02:54,780 --> 00:02:58,380 and I'm like wow, is this really a thing? 32 00:02:58,380 --> 00:03:02,920 Yeah, like the historical mysteries, or ancient aliens, or the unexplained files. 33 00:03:02,920 --> 00:03:06,280 Yeah, I hear these things and I ask, is this really unexplained? 34 00:03:06,280 --> 00:03:11,100 Well what about these reality shows where they investigate mysterious phenomena? 35 00:03:11,100 --> 00:03:14,880 Yeah, like the ghost hunting shows, where something weird always seems to happen. 36 00:03:14,880 --> 00:03:20,090 Yeah and it's like, is something weird actually happening, or is it just special effects or editing or whatever. 37 00:03:20,090 --> 00:03:22,784 I want it to be real because it's exciting, but at the same time, 38 00:03:22,784 --> 00:03:25,900 I don't want to be fooled into believing something that's not true. 39 00:03:25,900 --> 00:03:33,140 Well, definitely, television is a source of information that we all have to figure out how to process on our own. 40 00:03:34,440 --> 00:03:39,360 That can be a daunting task, because TV shows aren't there to educate and inform -- 41 00:03:39,360 --> 00:03:45,300 they're there to entertain; even the ones that bill themselves as science or history networks. 42 00:03:45,900 --> 00:03:50,940 How could that be? How could an education channel mislead us? 43 00:03:50,940 --> 00:03:56,560 We tend to forget that TV networks are for-profit businesses, not public services. 44 00:03:56,560 --> 00:04:00,800 Their motivation is to attract eyeball share and generate revenue for their advertisers. 45 00:04:00,800 --> 00:04:07,460 Whether the science or history that they present is real or not, simply isn't part of that equation. 46 00:04:07,740 --> 00:04:13,900 The easiest way for them to make a program fascinating is to go for cheap sensationalism. 47 00:04:13,900 --> 00:04:18,440 Create the appearance of mystery, the appearance of controversy. 48 00:04:18,440 --> 00:04:23,180 Present things as being "unsolved" or "baffling to scientists". 49 00:04:23,180 --> 00:04:28,980 Present fringe cranks with oddball theories as if they're real experts. 50 00:04:28,980 --> 00:04:30,400 That's not true. 51 00:04:30,400 --> 00:04:33,949 Sometimes we'll often show a real scientist to give the "conventional" view. 52 00:04:33,949 --> 00:04:36,760 It's great that you'll often present good information, 53 00:04:36,760 --> 00:04:40,400 but when you show it alongside bad information, as if they're equally valid, 54 00:04:40,400 --> 00:04:43,880 that's what we call "false balance", and it's a terrible way to inform. 55 00:04:43,880 --> 00:04:47,090 Why is it a terrible idea to give both sides of a story? 56 00:04:47,090 --> 00:04:49,540 Audiences are smart enough to decide for themselves. 57 00:04:49,540 --> 00:04:55,520 Giving two conflicting stories and saying "You decide" produces a confused viewer. 58 00:04:55,520 --> 00:05:00,380 Presenting what we actually know and how we know it produces an educated viewer. 59 00:05:00,380 --> 00:05:02,272 We're all products of the information we're given. 60 00:05:02,272 --> 00:05:05,940 You're just saying you want to be the arbiter of what's true and what's not. 61 00:05:05,940 --> 00:05:08,660 Why are your experts any more valid than ours? 62 00:05:08,660 --> 00:05:14,870 We work really hard to find the best people we can, people who have worked their whole careers, and you just want to shoot them down... 63 00:05:14,870 --> 00:05:23,360 (Argue, argue, argue...) 64 00:05:23,360 --> 00:05:28,980 The fact is, science communicators and TV producers have different motivations. 65 00:05:29,100 --> 00:05:34,560 When those motivations align, we get great programming; but when they don't… 66 00:05:37,020 --> 00:05:40,740 ...what we see onscreen might be make-believe. 67 00:05:40,740 --> 00:05:46,560 But even television isn't the biggest pipeline of unreliable information flowing straight into our brains. 68 00:05:46,780 --> 00:05:50,390 To find out what that is, let's go ask some more people. 69 00:05:52,480 --> 00:05:57,120 Here we are with a couple of friends now, Ron and Tyson. 70 00:05:57,130 --> 00:05:59,930 So where does most bad information come from these days? 71 00:05:59,930 --> 00:06:00,960 The Internet. 72 00:06:01,160 --> 00:06:02,160 The Internet. 73 00:06:02,160 --> 00:06:04,340 That seems to be where most of us get our news. 74 00:06:04,340 --> 00:06:06,580 But you have to go out of your way to find something reputable. 75 00:06:06,580 --> 00:06:10,860 Yeah, the stuff that comes through your social media feed, you don't know what the source is. 76 00:06:10,860 --> 00:06:15,400 If two of my friends on social media are debating something, they'll each send out a link to an article, 77 00:06:15,400 --> 00:06:18,420 the articles will say exactly the opposite thing. Which one's true? 78 00:06:18,420 --> 00:06:21,480 Everything is on the Internet, the true stuff, the false stuff. 79 00:06:21,480 --> 00:06:25,200 The thing is, I can guarantee no matter how crazy something seems, 80 00:06:25,200 --> 00:06:28,280 I can go on the Internet and find a source to support it. 81 00:06:28,280 --> 00:06:32,280 It sounds like using the Internet to figure out what's true can be pretty frustrating. 82 00:06:34,400 --> 00:06:39,060 This is a data center filled with web servers, where the Internet actually lives. 83 00:06:39,060 --> 00:06:42,550 It's got good websites, and garbage websites. 84 00:06:42,550 --> 00:06:47,490 But even with reputable news sites, the system for reporting science to the general public 85 00:06:47,490 --> 00:06:51,400 actually does favor lower quality information. 86 00:06:51,400 --> 00:06:58,120 That's right: any given science article on a consumer-focused website that describes the latest research 87 00:06:58,120 --> 00:07:01,020 is very likely misleading. 88 00:07:01,020 --> 00:07:02,520 And here's why: 89 00:07:05,300 --> 00:07:10,900 This line is the history of research in some scientific field. 90 00:07:10,900 --> 00:07:15,120 These circles are studies that were done over time. 91 00:07:15,130 --> 00:07:19,850 The big circles are larger, well designed studies, that have really good data, and probably 92 00:07:19,850 --> 00:07:22,100 give us the most reliable results. 93 00:07:22,100 --> 00:07:27,520 That's why most of these are along the line, which represents the true facts in this scientific field. 94 00:07:27,680 --> 00:07:31,520 Basic facts that get reinforced every time we take a second look. 95 00:07:31,530 --> 00:07:36,639 The better a study is, the more likely its results are to reflect the real science. 96 00:07:36,640 --> 00:07:45,020 Now, the smaller circles are smaller studies, less rigorous, and more susceptible to anomalous data. 97 00:07:45,080 --> 00:07:47,920 So we see some of these give us crazy results, 98 00:07:47,920 --> 00:07:51,780 farther away from what most of the best research has found. 99 00:07:51,780 --> 00:07:56,660 Now let's say you're the editor of a TV news program, looking for something interesting to report. 100 00:07:56,660 --> 00:07:59,320 Are you going to choose one of these here in the middle? 101 00:07:59,330 --> 00:08:02,410 Gravity still makes things fall, water is still wet? 102 00:08:02,410 --> 00:08:07,740 No, you're going to choose one of these outliers, because it seems to tell us something surprising, 103 00:08:07,740 --> 00:08:11,550 something interesting, something that really shakes things up. 104 00:08:11,550 --> 00:08:17,480 And sometimes, the PR departments of research institutions actually make this problem worse. 105 00:08:17,480 --> 00:08:22,080 Because they're trying to draw attention and funding to their institution. 106 00:08:22,080 --> 00:08:28,300 You don't do that with "Water is still wet", you do that with "One pill will cure all disease!" 107 00:08:28,300 --> 00:08:34,680 and "Invisibility cloaks are real!" so that's what they put in their press releases. 108 00:08:34,680 --> 00:08:36,080 The result? 109 00:08:36,080 --> 00:08:43,080 Many of the new science discoveries you hear about on the TV news, or read on a consumer-focused website, 110 00:08:43,080 --> 00:08:47,300 really are -- more than likely -- wrong. 111 00:08:48,760 --> 00:08:51,280 That can really blow your mind. 112 00:08:51,280 --> 00:08:56,040 We start to realize, wow, we really do get fed a lot of bad information, 113 00:08:56,040 --> 00:08:59,140 which shouldn't surprise anyone whose main source of news is Facebook. 114 00:08:59,140 --> 00:09:03,820 I feel like I need a trusted friend to help me navigate the fog. 115 00:09:03,820 --> 00:09:08,080 Because we can always rely on what our friends tell us, right? 116 00:09:11,400 --> 00:09:12,680 Well let's see about that. 117 00:09:12,680 --> 00:09:16,840 This is Lisa and Phil, we're talking about the kinds of things we learn from our friends. 118 00:09:16,840 --> 00:09:21,100 Last night, half of my friends were talking about this cleansing diet that they're all doing. 119 00:09:21,100 --> 00:09:23,540 With "amazing medical benefits"? 120 00:09:23,540 --> 00:09:27,180 I don't remember my doctor ever suggesting that I do anything like that. 121 00:09:27,180 --> 00:09:32,100 Did they tell you to eat this superfood, or to avoid that bad food? 122 00:09:32,100 --> 00:09:36,780 Well I had another friend tell me that I should do acupuncture for literally everything. 123 00:09:36,780 --> 00:09:39,880 But friends don't try to steer each other wrong. 124 00:09:39,880 --> 00:09:44,020 I trust my friends, and I know they won't intentionally give me bad advice, 125 00:09:44,020 --> 00:09:48,990 but sometimes you got to wonder if you're doing something just because everybody's doing it. 126 00:09:48,990 --> 00:09:53,180 How do I know whether something is true or not? 127 00:10:01,400 --> 00:10:02,280 Oh, thanks. 128 00:10:02,480 --> 00:10:03,420 My pleasure. 129 00:10:03,840 --> 00:10:07,000 Every weird thing you can think of, people do it. 130 00:10:07,000 --> 00:10:11,800 And a lot of them claim to be magically easy solutions to difficult problems. 131 00:10:11,800 --> 00:10:17,420 Purify your body, some new mental technique, lose weight really fast, 132 00:10:17,420 --> 00:10:24,880 all with this really simple new thing that promises to be a lot easier than the hard work you used to have to do. 133 00:10:32,200 --> 00:10:34,000 Sounds seductive, doesn't it? 134 00:10:34,000 --> 00:10:39,840 And I bet that the last time you went out with friends, you heard that at least one of them is doing at least one of those. 135 00:10:39,840 --> 00:10:43,500 Magically easy solutions to difficult problems. 136 00:10:43,500 --> 00:10:50,200 Everyone wants them, so they're very easy to sell, and we all want to believe in them. 137 00:10:50,200 --> 00:10:53,900 Unfortunately the facts aren't always so magical. 138 00:10:53,900 --> 00:10:57,660 Difficult problems are difficult because they're hard to solve. 139 00:10:57,660 --> 00:10:59,820 Losing weight is really hard. 140 00:10:59,820 --> 00:11:02,680 Aging is a painful reality. 141 00:11:02,680 --> 00:11:04,660 Getting rich is unlikely. 142 00:11:04,660 --> 00:11:12,880 And most of us are never going to look like movie stars because that's controlled a lot more by genetics than by behavior. 143 00:11:12,880 --> 00:11:16,980 The data shows that we can improve ourselves in many of these areas, 144 00:11:16,980 --> 00:11:21,860 but never as much as we wish, and only through a lot of really hard work. 145 00:11:21,860 --> 00:11:26,540 That's why it's such a snap for marketers to sell magically easy solutions, 146 00:11:26,540 --> 00:11:32,100 and why so many of our friends become deeply invested in them psychologically. 147 00:12:09,580 --> 00:12:14,200 I love that curiosity is one of our basic, instinctive characteristics. 148 00:12:14,200 --> 00:12:19,160 I love how it's taken us from making stone tools all the way to... 149 00:12:19,160 --> 00:12:21,900 landing humans on the surface of the moon. 150 00:12:21,900 --> 00:12:25,000 That's the power of curiosity. 151 00:12:44,560 --> 00:12:47,540 But the flip side is that it can get the better of us. 152 00:12:47,540 --> 00:12:52,000 We get mesmerized by sales pitches and buy things we don't need, 153 00:12:52,000 --> 00:12:57,200 we treat ourselves with alternative remedies that promise miracles but do nothing, 154 00:12:57,200 --> 00:13:01,920 and we devote time and energy believing all kinds of things that aren't true, 155 00:13:01,920 --> 00:13:07,780 all because we often fail to temper our curiosity with critical thinking. 156 00:13:13,760 --> 00:13:18,680 In my work as a science writer, I focus on separating science from pseudoscience. 157 00:13:18,680 --> 00:13:22,940 My job is to research the facts and find out what we really know. 158 00:13:26,320 --> 00:13:35,400 To help me do this, I've developed a set of principles I call the three C's: Challenge, Consider, and Conclude. 159 00:13:35,400 --> 00:13:42,000 To show you how these work, let's apply them to my favorite mystery, back in Death Valley. 160 00:14:32,760 --> 00:14:35,280 Well here we are, Racetrack Playa. 161 00:14:35,280 --> 00:14:40,640 It's a dry lake, 4 kilometers long, …and it's famous for rocks that move 162 00:14:40,640 --> 00:14:44,940 across its surface, all by themselves. 163 00:14:52,980 --> 00:14:58,019 We see the trails that they leave, but so far nobody's ever seen them move. 164 00:14:58,020 --> 00:15:01,000 They're called the sailing stones. 165 00:15:07,290 --> 00:15:08,280 So here's one of them. 166 00:15:08,280 --> 00:15:10,160 And you can see the trail that it left. 167 00:15:10,160 --> 00:15:14,400 And this is absolutely real, we've tracked their positions 168 00:15:14,400 --> 00:15:18,480 and we know for a fact that these rocks do move. 169 00:15:18,480 --> 00:15:24,980 This rock really did start off way down there, and it slid across the surface, all by itself 170 00:15:24,980 --> 00:15:26,220 to here. 171 00:15:26,980 --> 00:15:32,700 For 100 years, people had no idea what caused these stones to move. 172 00:15:32,700 --> 00:15:37,440 The closest thing to a science-based explanation anyone came up with 173 00:15:37,440 --> 00:15:43,780 was that strong winds would push the rocks when the mud was wet and slippery, 174 00:15:43,780 --> 00:15:49,040 something that's never been observed anywhere on Earth; the physics just don't make that possible. 175 00:15:49,040 --> 00:15:54,380 Some people were so confounded by it that they came up with some really far-out ideas. 176 00:15:54,380 --> 00:15:59,040 Somehow magnetic fields were involved, or gravity would shift, 177 00:15:59,040 --> 00:16:02,280 or aliens and UFOs were responsible, 178 00:16:02,280 --> 00:16:10,160 or people would even just throw out random words like "energy vortex" and hoped that that would somehow provide the explanation. 179 00:16:10,940 --> 00:16:13,400 The simple fact is that nobody had a clue. 180 00:16:14,900 --> 00:16:19,320 So let's apply our principles and see if we can understand this mystery. 181 00:16:22,660 --> 00:16:29,560 Step one, the first of our three C's, CHALLENGE the concept that we're curious about. 182 00:16:29,560 --> 00:16:36,660 Like, before it makes sense to ask about magnetic fields and telekinesis and aliens moving the rocks, 183 00:16:36,660 --> 00:16:39,140 let's first make sure about something. 184 00:16:39,140 --> 00:16:42,020 Are the rocks actually moving at all? 185 00:16:42,020 --> 00:16:46,180 You see, that's a question that we often fail to ask. 186 00:16:46,180 --> 00:16:51,029 Your friend is drinking a detox juice cleanse to remove toxins from her body; 187 00:16:51,029 --> 00:16:57,240 how often do we fail to ask whether these mysterious toxins are actually there to begin with? 188 00:16:57,720 --> 00:16:58,720 They're not. 189 00:16:58,860 --> 00:17:04,770 Or, a TV documentary gives us a new explanation for the disappearances in the Bermuda Triangle; 190 00:17:04,770 --> 00:17:11,140 how often do we fail to ask whether there actually are an unusual number of disappearances there? 191 00:17:11,400 --> 00:17:12,460 There aren't. 192 00:17:13,260 --> 00:17:16,880 There's a great maxim attributed to psychologist Ray Hyman: 193 00:17:16,880 --> 00:17:23,640 "Do not try to explain something until you're sure there is something to be explained." 194 00:17:23,640 --> 00:17:24,799 Let's try this out. 195 00:17:24,799 --> 00:17:29,250 Let's see if we can find something that makes a really popular, really compelling claim, 196 00:17:29,250 --> 00:17:33,149 and see if we can challenge it at this most basic level. 197 00:17:33,149 --> 00:17:38,120 Before trying to explain it, can we first verify whether it exists at all? 198 00:17:44,920 --> 00:17:46,000 Here's a good one. 199 00:17:46,009 --> 00:17:49,110 A lot of products promise to boost your immune system. 200 00:17:49,110 --> 00:17:54,180 And that's compelling, we'd all love to have a super-powered immune system and never get sick. 201 00:17:54,180 --> 00:17:58,740 We might be curious enough about this to ask how it works. 202 00:18:00,800 --> 00:18:04,980 But when we look into this, we quickly find out a disturbing fact. 203 00:18:06,440 --> 00:18:08,600 There's no such thing as boosting your immune system. 204 00:18:08,760 --> 00:18:11,860 Medically, the words are meaningless. 205 00:18:17,380 --> 00:18:20,169 Your immune system is a delicate balance. 206 00:18:20,169 --> 00:18:23,324 We want it to attack things like viruses and bacteria, 207 00:18:23,324 --> 00:18:27,600 but we don't want it so active that it attacks our own healthy tissue. 208 00:18:28,649 --> 00:18:33,160 When it does, that's called an autoimmune disease, and a lot of people suffer from them. 209 00:18:33,160 --> 00:18:37,700 Lupus and Rheumatoid Arthritis are just two of the more than 80 different 210 00:18:37,700 --> 00:18:42,240 "boosted immune systems", aka autoimmune diseases. 211 00:18:43,080 --> 00:18:45,660 They are not something you want. 212 00:18:47,680 --> 00:18:51,360 Fortunately, these aren't going to do anything. 213 00:18:57,580 --> 00:19:01,100 If you see a product like this, put it back. 214 00:19:01,100 --> 00:19:03,420 We challenged it, and it failed. 215 00:19:03,420 --> 00:19:06,640 Medically, there's no such thing as immune system boosting, 216 00:19:06,645 --> 00:19:09,500 so there's nothing here for us to have to explain. 217 00:19:39,440 --> 00:19:44,420 But when we challenged the story of the sailing stones from Racetrack Playa, 218 00:19:44,420 --> 00:19:47,789 we found out there is something to explain. 219 00:19:47,789 --> 00:19:49,240 They are moving. 220 00:19:49,240 --> 00:19:51,840 People have tracked them on GPS. 221 00:19:54,760 --> 00:19:59,360 It was important to wonder if these trails might have been created some other way, 222 00:19:59,360 --> 00:20:02,260 but no, we do have a real thing here. 223 00:20:05,460 --> 00:20:09,058 The sailing stones survived our initial challenge, 224 00:20:09,058 --> 00:20:13,840 so now it makes sense to proceed and try to figure out what's going on. 225 00:20:17,120 --> 00:20:23,700 The next step in doing that is the second of our three C's: CONSIDER alternate explanations. 226 00:20:30,140 --> 00:20:36,260 I want to find out everything I can about what work people have already done to solve this. 227 00:20:36,260 --> 00:20:40,580 Some of it might be a little odd, but the wider I can cast my net, 228 00:20:40,580 --> 00:20:46,000 the more likely I am to find the best work done by the smartest people. 229 00:20:51,980 --> 00:20:56,380 How does the average person on the street, who may not have any special knowledge, 230 00:20:56,380 --> 00:20:59,420 learn what the latest research says on a given topic? 231 00:20:59,420 --> 00:21:05,860 Well, no matter what question you're pondering, you can almost always come up with a few explanations to consider, 232 00:21:05,860 --> 00:21:09,800 just by starting somewhere obvious like Wikipedia. 233 00:21:09,800 --> 00:21:12,220 Often, your choices boil down to two. 234 00:21:12,220 --> 00:21:18,060 These are usually a boring science-based explanation, and an exciting alternate explanation, 235 00:21:18,060 --> 00:21:22,600 promoted by a small number of personalities, often non-scientists, 236 00:21:22,600 --> 00:21:26,020 but who might be on TV or writing books. 237 00:21:26,980 --> 00:21:32,060 For example, the Apollo 11 astronauts saw something following them when they flew to the moon. 238 00:21:32,100 --> 00:21:37,080 The science-based explanation is that they soon realized it was one of four adapter panels 239 00:21:37,080 --> 00:21:41,820 that fit between the S-IVB third stage and the lunar module. 240 00:21:41,820 --> 00:21:47,000 The exciting alternate explanation is that it must have been an alien spacecraft. 241 00:21:52,500 --> 00:21:56,040 That's two possible explanations for us to consider. 242 00:21:56,040 --> 00:21:59,420 How does the average person know which one to trust? 243 00:22:02,200 --> 00:22:04,360 There's one piece of advice I always give. 244 00:22:04,360 --> 00:22:09,600 Go with the experts, the real working scientists, who have studied this their entire careers, 245 00:22:09,600 --> 00:22:13,980 and have worked closely with other researchers in the same field worldwide, 246 00:22:13,980 --> 00:22:16,640 and developed a pretty strong knowledge base. 247 00:22:17,700 --> 00:22:21,460 Aliens did not follow the Apollo astronauts to the moon. 248 00:22:22,960 --> 00:22:27,180 Sometimes this advice means depending on what some government agency says, 249 00:22:27,180 --> 00:22:30,940 or some other establishment that you might be inclined to distrust. 250 00:22:30,940 --> 00:22:33,820 That's true, and that can be a valid concern. 251 00:22:33,820 --> 00:22:38,640 But remember what we're trying to do here: we're collecting ideas to consider. 252 00:22:38,640 --> 00:22:44,100 We'd be foolish to dismiss the one that most professional experts in the field agree on. 253 00:22:45,980 --> 00:22:49,560 Distrust of authority goes back throughout history. 254 00:22:49,560 --> 00:22:56,820 The Roman statesman Cicero said "There is nothing so absurd that some philosopher has not already said it." 255 00:22:56,820 --> 00:23:00,660 Even the Royal Society's motto is "Nullius in verba" 256 00:23:00,660 --> 00:23:05,020 meaning "Don't take anybody's word for anything." 257 00:23:05,020 --> 00:23:13,300 So there's a popular notion that trusting an authoritative source is automatically a logical fallacy called the Appeal to Authority. 258 00:23:13,300 --> 00:23:17,080 Being in a position of authority doesn't automatically make you right. 259 00:23:17,080 --> 00:23:23,940 But the logical fallacy refers to false authorities: Celebrity spokespeople, or snake oil salesmen 260 00:23:23,940 --> 00:23:29,240 who pose wearing authoritative-looking white labcoats, when they're not actually doctors. 261 00:23:29,240 --> 00:23:35,280 But real experts in any field truly do represent the core of our knowledge in that field. 262 00:23:35,280 --> 00:23:39,889 We landed humans on the moon because the scientists and engineers spent years working together 263 00:23:39,889 --> 00:23:43,000 with the best knowledge we had. 264 00:24:13,280 --> 00:24:19,200 When we need heart surgery we go to a real cardiovascular surgeon who went to a real medical school. 265 00:24:19,200 --> 00:24:24,540 When we take a trip on a plane we want a real pilot with a legitimate pilot's license. 266 00:24:24,540 --> 00:24:30,900 So when we ask a science question, it is not irrational to go to a science expert. 267 00:24:34,200 --> 00:24:39,580 I always advise the average person to go with the experts, instead of the media personalities. 268 00:24:39,580 --> 00:24:45,800 Maybe you won't always be right, but you will be right far more often than you're wrong. 269 00:24:50,280 --> 00:24:55,140 For another example, let's look at one subject where pop culture is filled with misinformation: 270 00:24:55,149 --> 00:24:56,349 food! 271 00:24:56,349 --> 00:25:00,740 Specifically, genetically engineered crops, like these sugar beets. 272 00:25:00,740 --> 00:25:05,260 Demonizing modern agriculture has become a tremendously profitable food fad, 273 00:25:05,260 --> 00:25:12,000 and as a result, non-food-scientists pressure us with misinformation from a bewildering number of angles. 274 00:25:12,000 --> 00:25:16,880 Packaging experts use labels that suggest GMOs should be avoided; 275 00:25:16,889 --> 00:25:22,879 Bookstores are full of bestsellers by dieting or cooking gurus cashing in on the fad; 276 00:25:22,880 --> 00:25:27,760 Restaurants proudly display signage that they won't serve these foods either. 277 00:25:27,760 --> 00:25:30,900 Here's where you find yourself having to make a choice. 278 00:25:30,900 --> 00:25:35,800 There's a huge amount of noise coming from self-proclaimed pop foodie experts, 279 00:25:35,800 --> 00:25:42,160 promoting the idea that genetically engineered crops are dangerous to us or to the environment. 280 00:25:42,160 --> 00:25:46,260 Yet, those products remain a staple of our food supply. 281 00:25:46,260 --> 00:25:49,726 Farmers keep growing them, food producers keep using them, 282 00:25:49,726 --> 00:25:55,300 and virtually every product found in the supermarket contains some GMO ingredient. 283 00:25:57,500 --> 00:26:02,860 Hundreds of billions of GMO meals have been served over the past 50 years, 284 00:26:02,860 --> 00:26:09,690 and not a single health problem -- not one -- has ever been traced to the crop's genome. 285 00:26:09,690 --> 00:26:14,580 It would seem there's a huge amount of evidence that all this non-expert advice 286 00:26:14,580 --> 00:26:20,960 might be driven less by real science, and more by marketing and sensationalism. 287 00:26:25,000 --> 00:26:31,460 So let's see what the real experts have to say: the farmers, the regulators, the testers, the agriculturalists. 288 00:26:31,460 --> 00:26:36,440 All the world's most experienced experts at figuring out how to best feed the world. 289 00:26:36,440 --> 00:26:40,840 Turns out some of the tools are new, like gene splicing with CRISPR-Cas9, 290 00:26:40,840 --> 00:26:46,400 but the basic techniques have been a staple of agriculture for thousands of years. 291 00:26:47,980 --> 00:26:55,020 Apples, bananas, melons, even sugar; they're all products of genetic engineering at some level. 292 00:26:55,020 --> 00:26:59,340 You wouldn't even recognize kale if you saw what it looked like 2000 years ago, 293 00:26:59,340 --> 00:27:03,460 before we started cross-pollinating it to make it palatable. 294 00:27:07,980 --> 00:27:13,160 It does stand to reason that graduate school, years in the field, years in the lab, 295 00:27:13,160 --> 00:27:18,320 years of working with the best minds, is going to produce a better informed expert. 296 00:27:18,320 --> 00:27:23,720 If you want to be right more often than wrong, go with what the real experts say. 297 00:27:29,540 --> 00:27:32,200 So the expert opinion on the sailing stones? 298 00:27:32,200 --> 00:27:37,940 Well, geologists had published a bit, but nobody had ever managed to collect any direct evidence. 299 00:27:37,940 --> 00:27:42,519 The best guess was that strong winds would push the rocks hard enough to unstick them 300 00:27:42,519 --> 00:27:44,759 and slide them across the wet mud. 301 00:27:44,759 --> 00:27:50,539 It wasn't very persuasive; we just never had enough data to come up with anything better. 302 00:27:50,539 --> 00:27:52,599 I wanted to see if I could learn anything new. 303 00:27:52,600 --> 00:27:58,560 So I came here with some friends way back in 2001, and luckily, I found something. 304 00:28:01,160 --> 00:28:03,080 This is the video I took. 305 00:28:03,080 --> 00:28:09,060 It was winter, when water from snow melt and rain formed a shallow lake at the south end of the playa. 306 00:28:09,060 --> 00:28:12,259 The morning wind was strong and ice cold. 307 00:28:12,259 --> 00:28:17,799 The whole lake was actually being pushed along by the wind at almost walking speed. 308 00:28:17,799 --> 00:28:23,970 It's not really visible in this low-quality video, but we could see great sheets of thin ice out on the lake. 309 00:28:23,970 --> 00:28:27,200 The sun had been on us for an hour and it was above freezing, 310 00:28:27,200 --> 00:28:31,840 but think how it must have been just before dawn with that wind screaming. 311 00:28:31,840 --> 00:28:35,466 Wind alone might not be able to move a rock that's planted in mud, 312 00:28:35,466 --> 00:28:38,700 but what if something solid pushes it? 313 00:28:38,700 --> 00:28:43,700 The rock is in the shallow water, and so are these great sheets of ice. 314 00:28:43,710 --> 00:28:47,869 When the wind gets that ice moving, that's a lot of momentum. 315 00:28:47,869 --> 00:28:52,739 The solid ice takes hold of those rocks, and it's the mud that gives way. 316 00:28:52,740 --> 00:29:00,780 The rocks drag across the playa, leaving tracks wherever those meandering ice sheets take them. 317 00:29:08,620 --> 00:29:14,360 One lucky morning, and I found myself with a new alternate explanation in hand. 318 00:29:16,160 --> 00:29:21,780 I'd challenged and I'd considered, and now it was time for the final C: 319 00:29:21,780 --> 00:29:25,140 to CONCLUDE which explanation fits best. 320 00:29:25,140 --> 00:29:28,740 Could it be the ice sheets that I saw? 321 00:29:28,740 --> 00:29:32,940 Is it magnetic fields moving these non-magnetic rocks around? 322 00:29:32,940 --> 00:29:38,340 Was the wind unsticking them from the mud and sliding them across the ground? 323 00:29:42,860 --> 00:29:48,260 All of these explanations -- except the ice sheets -- have one very important thing wrong with them, 324 00:29:48,260 --> 00:29:51,060 and it makes it easy to cross them off the list. 325 00:29:51,070 --> 00:29:55,860 They'd all require some tweak to our understanding of the world to make them work. 326 00:29:55,860 --> 00:30:01,960 If aliens were moving the stones, we'd need to change our model of the world to include visiting aliens. 327 00:30:01,960 --> 00:30:07,000 If energy vortexes were doing it, we'd need to live in a world where there's such a thing as... 328 00:30:07,000 --> 00:30:11,720 well, whatever an "energy vortex" is supposed to be. 329 00:30:11,720 --> 00:30:15,080 What's a good way to assess these kinds of explanations? 330 00:30:15,080 --> 00:30:18,340 If only there was some tool... 331 00:30:33,380 --> 00:30:39,480 You may have heard of Occam's razor, named for the Franciscan philosopher William of Ockham. 332 00:30:39,480 --> 00:30:44,540 It's a tool that can help us decide which of several possibilities is most likely true. 333 00:30:44,540 --> 00:30:47,919 It's been stated in a number of different ways, but the one I like best is 334 00:30:47,919 --> 00:30:54,440 "Among competing hypotheses, the one with the fewest assumptions should be selected." 335 00:30:54,440 --> 00:30:59,799 An "assumption" refers to some condition that's required to make the hypothesis possible. 336 00:30:59,800 --> 00:31:05,300 If we see some strange light in the sky, one option is that it's an alien spaceship. 337 00:31:05,300 --> 00:31:11,340 For this to be possible, we'd first need to accept the assumption that alien spaceships visit us -- 338 00:31:11,340 --> 00:31:14,640 a pretty big change from what we currently understand. 339 00:31:14,640 --> 00:31:19,160 The other option, that the light is simply something we don't personally recognize, 340 00:31:19,160 --> 00:31:25,360 requires no new assumptions about the world, and is therefore most likely correct. 341 00:31:25,360 --> 00:31:32,700 In short, Occam's razor tells us that ideas which only work if some magical new thing is added to the world, 342 00:31:32,700 --> 00:31:34,480 are probably wrong. 343 00:31:35,600 --> 00:31:37,960 Here's another example. 344 00:31:37,960 --> 00:31:40,460 We've all seen photographs like these. 345 00:31:40,460 --> 00:31:45,240 These circles weren't visible when the picture was taken, but here they are now. 346 00:31:45,240 --> 00:31:48,800 There are two competing hypotheses for what these are. 347 00:31:48,800 --> 00:31:55,060 Some people think they represent ghostly presences, and they call them orbs, or spirit orbs. 348 00:31:55,060 --> 00:31:59,440 Others think they're simply particles of dust, lit up by the camera flash, 349 00:31:59,440 --> 00:32:03,600 and appear as large circles simply because they're out of focus. 350 00:32:03,600 --> 00:32:09,120 Occam's razor can help us determine which hypothesis is more likely true. 351 00:32:10,140 --> 00:32:15,560 The ghost explanation requires us to assume that ghosts are a known thing. 352 00:32:15,560 --> 00:32:17,540 Unfortunately, we don't know that. 353 00:32:17,540 --> 00:32:20,680 We've never caught one. We don't know what properties they might have. 354 00:32:20,680 --> 00:32:24,960 We don't even have a theory that might support the possibility of their existence. 355 00:32:24,980 --> 00:32:31,720 So to accept the ghost explanation of orb photos, we'd have to make a new assumption. 356 00:32:33,160 --> 00:32:37,720 But the dust theory relies only on things that are well known to exist. 357 00:32:37,720 --> 00:32:43,700 Dust does get illuminated by a camera flash, which we can simulate with this light here. 358 00:32:46,260 --> 00:32:52,000 Dust does appear to be a large circle when it's out of focus, and brightly illuminated. 359 00:33:07,340 --> 00:33:12,820 Since we don't need to introduce any new assumptions, Occam's razor tells us the dust theory is 360 00:33:12,820 --> 00:33:16,840 probably the better explanation for orb photos. 361 00:33:20,340 --> 00:33:23,960 So, did space aliens move these rocks? 362 00:33:23,960 --> 00:33:27,300 Just think of all the new assumptions that would call for. 363 00:33:28,280 --> 00:33:30,339 No, it wasn't aliens. 364 00:33:30,340 --> 00:33:36,900 Occam's razor also tells us that it probably wasn't psychic energies or vortexes or other powers 365 00:33:36,900 --> 00:33:41,500 that would require us to overhaul our understanding of nature. 366 00:33:41,500 --> 00:33:47,759 But we already know for a fact that ice forms here, and that wind blows those ice sheets around. 367 00:33:47,760 --> 00:33:51,580 Those conditions are real, they're not new assumptions. 368 00:33:51,580 --> 00:33:57,020 We also know that ice moves rocks; if icebound rocks can carve Yosemite Valley, 369 00:33:57,020 --> 00:34:00,610 they can certainly drag a trail in some mud. 370 00:34:00,610 --> 00:34:07,800 The ice sheet hypothesis dovetails perfectly with facts about the world that we already know are true. 371 00:34:12,820 --> 00:34:22,060 Sure enough, in 2014, a group of scientists proved that this is, in fact, exactly what causes the sailing stones to move. 372 00:34:22,060 --> 00:34:27,720 They installed time-lapse cameras and a remote weather station right up there on that hillside. 373 00:34:27,720 --> 00:34:34,620 They placed fifteen GPS-equipped stones on the playa surface, then collected data for two years. 374 00:34:34,620 --> 00:34:39,920 Finally they caught the stones in action, as sheets of ice pushed the rocks around, 375 00:34:39,920 --> 00:34:43,840 and were captured in these time-lapse photos. 376 00:34:49,480 --> 00:34:53,060 Finding out that my solution was the true one was exciting. 377 00:34:53,060 --> 00:34:56,940 Solving a mystery, and getting it right, is pretty fun. 378 00:34:56,940 --> 00:35:01,220 It's also empowering, and inspires you to want to know more. 379 00:35:01,220 --> 00:35:06,180 I had the very best tool: I knew the basic principles to follow. 380 00:35:06,180 --> 00:35:07,930 They really do work. 381 00:35:07,930 --> 00:35:12,920 You may not be right every time, but you will be right most of the time. 382 00:35:17,980 --> 00:35:21,940 The Principles of Curiosity are basically the scientific method. 383 00:35:21,950 --> 00:35:24,410 Some of you watching might have recognized it. 384 00:35:24,410 --> 00:35:32,580 We challenge and falsify until we have a reliable observation, for which we can then form provisional explanations. 385 00:35:32,580 --> 00:35:38,980 We consider and test those explanations, and finally we conclude which one fits best. 386 00:35:38,980 --> 00:35:42,980 And that conclusion is always in motion. 387 00:35:45,500 --> 00:35:50,680 We might get better data tomorrow, it might allow us to improve our conclusion. 388 00:35:50,680 --> 00:35:57,000 Our ability to understand things is driven, at its core, by our basic curiosity. 389 00:35:57,000 --> 00:36:06,140 The scientific method is a way to steer our curiosity, and keep it on course to the best of our limited, human ability. 390 00:36:06,140 --> 00:36:09,220 A lot of times people will ask me why. 391 00:36:09,220 --> 00:36:15,760 Why shouldn't I believe in ghosts, or psychic powers, or miracle foods, or alternative medicine? 392 00:36:15,760 --> 00:36:19,540 What's the harm if I enjoy these things and they bring me comfort? 393 00:36:19,540 --> 00:36:23,520 After all, such things bring meaning and comfort to a lot of people. 394 00:36:23,520 --> 00:36:31,290 But happiness and enlightenment are all around us in our world; you don't have to turn to pseudoscience to find them. 395 00:36:31,290 --> 00:36:36,760 Searching for meaning in reality is far more likely to yield results. 396 00:36:36,760 --> 00:36:38,080 Test your beliefs. 397 00:36:38,080 --> 00:36:39,920 Subject them to scrutiny. 398 00:36:39,920 --> 00:36:46,980 Immunizing yourself against misinformation is more important than many of us ever stop to think. 399 00:36:46,980 --> 00:36:51,660 We make important life decisions based on what we think we know. 400 00:36:51,660 --> 00:36:55,580 Making the right decisions is how humanity advances. 401 00:36:57,420 --> 00:37:01,460 The tools of science have served us pretty well in this regard. 402 00:37:01,460 --> 00:37:05,550 We've learned a lot, and improved our lives immeasurably. 403 00:37:05,550 --> 00:37:11,420 Think of how much more we can do when we can better judge what's real from what's not. 404 00:37:11,420 --> 00:37:19,700 Longer life, happiness, a cleaner planet, technology, and peace are driven by the engine of science, 405 00:37:19,720 --> 00:37:24,900 and fired by the fuel of our curiosity. 406 00:37:41,480 --> 00:37:47,520 What makes a rocket ship fly? 407 00:37:47,520 --> 00:37:54,320 How far are those lights in the sky? 408 00:37:54,320 --> 00:38:05,560 Isn't there some way That I could go up there too? 409 00:38:05,560 --> 00:38:11,260 Things I can touch must be real 410 00:38:11,260 --> 00:38:17,340 But what about feelings I feel? 411 00:38:17,340 --> 00:38:30,020 So many mysteries Conceal secrets I want to know. 412 00:38:30,020 --> 00:38:35,540 A new idea, a new technique 413 00:38:35,540 --> 00:38:41,000 Threaten to turn me into a geek 414 00:38:41,000 --> 00:38:47,420 Love the old stories so full of mystique 415 00:38:47,420 --> 00:38:52,520 Tempting me to learn. 416 00:38:52,520 --> 00:38:58,400 Open up, let me in, let me see 417 00:38:58,400 --> 00:39:04,200 The wonders you're hiding from me 418 00:39:04,200 --> 00:39:14,720 I've got a little curiosity And possibly you've got some too. 419 00:39:15,940 --> 00:39:37,300 I've got a little curiosity And possibly you've got some too.