1 00:00:06,760 --> 00:00:09,160 Are you afraid of black cats? 2 00:00:09,160 --> 00:00:11,890 Would you open an umbrella indoors? 3 00:00:11,890 --> 00:00:15,552 And how do you feel about the number thirteen? 4 00:00:15,552 --> 00:00:17,299 Whether or not you believe in them, 5 00:00:17,299 --> 00:00:20,650 you're probably familiar with a few of these superstitions. 6 00:00:20,650 --> 00:00:23,600 So how did it happen that people all over the world 7 00:00:23,600 --> 00:00:25,200 knock on wood, 8 00:00:25,200 --> 00:00:28,749 or avoid stepping on sidewalk cracks? 9 00:00:28,749 --> 00:00:31,711 Well, although they have no basis in science, 10 00:00:31,711 --> 00:00:35,020 many of these weirdly specific beliefs and practices 11 00:00:35,020 --> 00:00:39,400 do have equally weird and specific origins. 12 00:00:39,400 --> 00:00:41,850 Because they involve supernatural causes, 13 00:00:41,850 --> 00:00:45,501 it's no surprise that many superstitions are based in religion. 14 00:00:45,501 --> 00:00:50,550 For example. the number thirteen was associated with the biblical Last Supper, 15 00:00:50,550 --> 00:00:53,682 where Jesus Christ dined with his twelve disciples 16 00:00:53,682 --> 00:00:57,720 just before being arrested and crucified. 17 00:00:57,720 --> 00:01:02,462 The resulting idea that having thirteen people at a table was bad luck 18 00:01:02,462 --> 00:01:08,142 eventually expanded into thirteen being an unlucky number in general. 19 00:01:08,142 --> 00:01:12,821 Now, this fear of the number thirteen, called triskaidekaphobia, 20 00:01:12,821 --> 00:01:18,262 is so common that many buildings around the world skip the thirteenth floor, 21 00:01:18,262 --> 00:01:22,102 with the numbers going straight from twelve to fourteen. 22 00:01:22,102 --> 00:01:26,361 Of course, many people consider the story of the Last Supper to be true 23 00:01:26,361 --> 00:01:29,360 but other superstitions come from religious traditions 24 00:01:29,360 --> 00:01:33,033 that few people believe in or even remember. 25 00:01:33,033 --> 00:01:37,793 Knocking on wood is thought to come from the folklore of the ancient Indo-Europeans 26 00:01:37,793 --> 00:01:40,733 or possibly people who predated them 27 00:01:40,733 --> 00:01:44,253 who believed that trees were home to various spirits. 28 00:01:44,253 --> 00:01:46,677 Touching a tree would invoke the protection 29 00:01:46,677 --> 00:01:50,107 or blessing of the spirit within. 30 00:01:50,107 --> 00:01:52,372 And somehow, 31 00:01:52,372 --> 00:01:56,197 this tradition survived long after belief in these spirits had faded away. 32 00:01:56,197 --> 00:02:00,237 Many superstitions common today in countries from Russia to Ireland 33 00:02:00,237 --> 00:02:05,813 are thought to be remnants of the pagan religions that Christianity replaced. 34 00:02:05,813 --> 00:02:08,693 But not all superstitions are religious. 35 00:02:08,693 --> 00:02:13,313 Some are just based on unfortunate coincidences and associations. 36 00:02:13,313 --> 00:02:16,453 For example, many Italians fear the number 17 37 00:02:16,453 --> 00:02:23,284 because the Roman numeral XVII can be rearranged to form the word vixi, 38 00:02:23,284 --> 00:02:25,633 meaning my life had ended. 39 00:02:25,633 --> 00:02:27,754 Similarly, the word for the number four 40 00:02:27,754 --> 00:02:30,494 sounds almost identical to the word for death 41 00:02:30,494 --> 00:02:32,044 in Cantonese, 42 00:02:32,044 --> 00:02:33,774 as well as languages like Japanese 43 00:02:33,774 --> 00:02:37,705 and Korean that have borrowed Chinese numerals. 44 00:02:37,705 --> 00:02:41,274 And since the number one also sounds like the word for must, 45 00:02:41,274 --> 00:02:45,383 the number fourteen sounds like the phrase must die. 46 00:02:45,383 --> 00:02:50,294 That's a lot of numbers for elevators and international hotels to avoid. 47 00:02:50,294 --> 00:02:51,414 And believe it or not, 48 00:02:51,414 --> 00:02:53,994 some superstitions actually make sense, 49 00:02:53,994 --> 00:02:58,174 or at least they did until we forgot their original purpose. 50 00:02:58,174 --> 00:03:03,185 For example, theater scenery used to consist of large painted backdrops, 51 00:03:03,185 --> 00:03:07,925 raised and lowered by stagehands who would whistle to signal each other. 52 00:03:07,925 --> 00:03:11,325 Absentminded whistles from other people could cause an accident. 53 00:03:11,325 --> 00:03:16,694 But the taboo against whistling backstage still exists today, 54 00:03:16,694 --> 00:03:20,576 long after the stagehands started using radio headsets. 55 00:03:20,576 --> 00:03:24,345 Along the same lines, lighting three cigarettes from the same match 56 00:03:24,345 --> 00:03:29,565 really could cause bad luck if you were a soldier in a foxhole 57 00:03:29,565 --> 00:03:34,586 where keeping a match lit too long could draw attention from an enemy sniper. 58 00:03:34,586 --> 00:03:37,458 Most smokers no longer have to worry about snipers, 59 00:03:37,458 --> 00:03:39,636 but the superstition lives on. 60 00:03:39,636 --> 00:03:42,596 So why do people cling to these bits of forgotten religions, 61 00:03:42,596 --> 00:03:43,486 coincidences, 62 00:03:43,486 --> 00:03:45,376 and outdated advice? 63 00:03:45,376 --> 00:03:48,137 Aren't they being totally irrational? 64 00:03:48,137 --> 00:03:50,077 Well, yes, but for many people, 65 00:03:50,077 --> 00:03:54,816 superstitions are based more on cultural habit than conscious belief. 66 00:03:54,816 --> 00:03:59,027 After all, no one is born knowing to avoid walking under ladders 67 00:03:59,027 --> 00:04:00,717 or whistling indoors, 68 00:04:00,717 --> 00:04:04,743 but if you grow up being told by your family to avoid these things, 69 00:04:04,743 --> 00:04:06,846 chances are they'll make you uncomfortable, 70 00:04:06,846 --> 00:04:11,208 even after you logically understand that nothing bad will happen. 71 00:04:11,208 --> 00:04:14,838 And since doing something like knocking on wood doesn't require much effort, 72 00:04:14,838 --> 00:04:19,946 following the superstition is often easier than consciously resisting it. 73 00:04:19,946 --> 00:04:23,696 Besides, superstitions often do seem to work. 74 00:04:23,696 --> 00:04:27,508 Maybe you remember hitting a home run while wearing your lucky socks. 75 00:04:27,508 --> 00:04:29,947 This is just our psychological bias at work. 76 00:04:29,947 --> 00:04:33,417 You're far less likely to remember all the times you struck out 77 00:04:33,417 --> 00:04:35,448 while wearing the same socks. 78 00:04:35,448 --> 00:04:39,008 But believing that they work could actually make you play better 79 00:04:39,008 --> 00:04:43,697 by giving you the illusion of having greater control over events. 80 00:04:43,697 --> 00:04:48,369 So in situations where that confidence can make a difference, like sports, 81 00:04:48,369 --> 00:04:52,838 those crazy superstitions might not be so crazy after all.