1 00:00:03,646 --> 00:00:06,612 So, this is my grandfather, 2 00:00:06,612 --> 00:00:08,113 Salman Schocken, 3 00:00:08,113 --> 00:00:12,550 who was born into a poor and uneducated family 4 00:00:12,550 --> 00:00:15,987 with six children to feed, 5 00:00:15,987 --> 00:00:19,683 and when he was 14 years old, he was forced to 6 00:00:19,683 --> 00:00:23,643 drop out of school in order to help put bread on the table. 7 00:00:23,643 --> 00:00:27,063 He never went back to school. 8 00:00:27,063 --> 00:00:31,210 Instead, he went on to build a glittering empire 9 00:00:31,210 --> 00:00:33,318 of department stores. 10 00:00:33,318 --> 00:00:36,571 Salman was the consummate perfectionist, 11 00:00:36,571 --> 00:00:39,135 and every one of his stores was a jewel 12 00:00:39,135 --> 00:00:41,064 of Bauhaus architecture. 13 00:00:41,064 --> 00:00:44,254 He was also the ultimate self-learner, 14 00:00:44,254 --> 00:00:47,157 and like everything else, he did it in grand style. 15 00:00:47,157 --> 00:00:49,845 He surrounded himself with an entourage 16 00:00:49,845 --> 00:00:53,232 of young, unknown scholars like Martin Buber 17 00:00:53,232 --> 00:00:56,371 and Shai Agnon and Franz Kafka, 18 00:00:56,371 --> 00:00:59,296 and he paid each one of them a monthly salary 19 00:00:59,296 --> 00:01:02,347 so that they could write in peace. 20 00:01:02,347 --> 00:01:07,284 And yet, in the late '30s, Salman saw what's coming. 21 00:01:07,284 --> 00:01:10,598 He fled Germany, together with his family, 22 00:01:10,598 --> 00:01:12,687 leaving everything else behind. 23 00:01:12,687 --> 00:01:15,897 His department stores confiscated, 24 00:01:15,897 --> 00:01:18,986 he spent the rest of his life in a relentless pursuit 25 00:01:18,986 --> 00:01:21,455 of art and culture. 26 00:01:21,455 --> 00:01:23,394 This high school dropout 27 00:01:23,394 --> 00:01:25,674 died at the age of 82, 28 00:01:25,674 --> 00:01:29,803 a formidable intellectual, cofounder and first CEO 29 00:01:29,803 --> 00:01:31,948 of the Hebrew University of Jerusalem, 30 00:01:31,948 --> 00:01:33,712 and founder of Schocken Books, 31 00:01:33,712 --> 00:01:37,083 an acclaimed imprint that was later acquired 32 00:01:37,083 --> 00:01:38,753 by Random House. 33 00:01:38,753 --> 00:01:42,729 Such is the power of self-study. 34 00:01:42,729 --> 00:01:45,245 And these are my parents. 35 00:01:45,245 --> 00:01:49,292 They too did not enjoy the privilege of college education. 36 00:01:49,292 --> 00:01:53,263 They were too busy building a family and a country. 37 00:01:53,263 --> 00:01:57,291 And yet, just like Salman, they were lifelong, 38 00:01:57,291 --> 00:02:01,049 tenacious self-learners, and our home was stacked 39 00:02:01,049 --> 00:02:05,212 with thousands of books, records and artwork. 40 00:02:05,212 --> 00:02:07,608 I remember quite vividly my father telling me 41 00:02:07,608 --> 00:02:12,440 that when everyone in the neighborhood will have a TV set, 42 00:02:12,440 --> 00:02:17,058 then we'll buy a normal F.M. radio. (Laughter) 43 00:02:17,058 --> 00:02:20,087 And that's me, 44 00:02:20,087 --> 00:02:21,811 I was going to say holding my first abacus, 45 00:02:21,811 --> 00:02:24,822 but actually holding what my father would consider 46 00:02:24,822 --> 00:02:27,774 an ample substitute to an iPad. (Laughter) 47 00:02:27,774 --> 00:02:31,436 So one thing that I took from home is this notion 48 00:02:31,436 --> 00:02:34,277 that educators don't necessarily have to teach. 49 00:02:34,277 --> 00:02:37,506 Instead, they can provide an environment and resources 50 00:02:37,506 --> 00:02:42,654 that tease out your natural ability to learn on your own. 51 00:02:42,654 --> 00:02:46,748 Self-study, self-exploration, self-empowerment: 52 00:02:46,748 --> 00:02:50,068 these are the virtues of a great education. 53 00:02:50,068 --> 00:02:54,263 So I'd like to share with you a story about a self-study, 54 00:02:54,263 --> 00:02:56,817 self-empowering computer science course 55 00:02:56,817 --> 00:03:01,003 that I built, together with my brilliant colleague Noam Nisan. 56 00:03:01,003 --> 00:03:03,760 As you can see from the pictures, both Noam and I 57 00:03:03,760 --> 00:03:07,178 had an early fascination with first principles, 58 00:03:07,178 --> 00:03:08,700 and over the years, as our knowledge of 59 00:03:08,700 --> 00:03:12,275 science and technology became more sophisticated, 60 00:03:12,275 --> 00:03:15,471 this early awe with the basics 61 00:03:15,471 --> 00:03:17,571 has only intensified. 62 00:03:17,571 --> 00:03:21,270 So it's not surprising that, about 12 years ago, when 63 00:03:21,270 --> 00:03:24,752 Noam and I were already computer science professors, 64 00:03:24,752 --> 00:03:28,504 we were equally frustrated by the same phenomenon. 65 00:03:28,504 --> 00:03:31,322 As computers became increasingly more complex, 66 00:03:31,322 --> 00:03:34,526 our students were losing the forest for the trees, 67 00:03:34,526 --> 00:03:37,613 and indeed, it is impossible to connect 68 00:03:37,613 --> 00:03:40,255 with the soul of the machine if you interact 69 00:03:40,255 --> 00:03:43,664 with a black box P.C. or a Mac which is shrouded 70 00:03:43,664 --> 00:03:47,040 by numerous layers of closed, proprietary software. 71 00:03:47,040 --> 00:03:50,730 So Noam and I had this insight that if we want our students 72 00:03:50,730 --> 00:03:52,749 to understand how computers work, 73 00:03:52,749 --> 00:03:55,837 and understand it in the marrow of their bones, 74 00:03:55,837 --> 00:03:57,398 then perhaps the best way to go about it 75 00:03:57,398 --> 00:04:01,992 is to have them build a complete, working, 76 00:04:01,992 --> 00:04:05,704 general-purpose, useful computer, hardware and software, 77 00:04:05,704 --> 00:04:09,234 from the ground up, from first principles. 78 00:04:09,234 --> 00:04:13,442 Now, we had to start somewhere, and so Noam and I 79 00:04:13,442 --> 00:04:16,932 decided to base our cathedral, so to speak, 80 00:04:16,932 --> 00:04:20,071 on the simplest possible building block, 81 00:04:20,071 --> 00:04:22,872 which is something called NAND. 82 00:04:22,872 --> 00:04:26,810 It is nothing more than a trivial logic gate 83 00:04:26,810 --> 00:04:29,848 with four input-output states. 84 00:04:29,848 --> 00:04:32,514 So we now start this journey by telling our students 85 00:04:32,514 --> 00:04:34,582 that God gave us NAND — (Laughter) — 86 00:04:34,582 --> 00:04:38,567 and told us to build a computer, and when we asked how, 87 00:04:38,567 --> 00:04:41,751 God said, "One step at a time." 88 00:04:41,751 --> 00:04:44,844 And then, following this advice, we start 89 00:04:44,844 --> 00:04:47,803 with this lowly, humble NAND gate, 90 00:04:47,803 --> 00:04:49,743 and we walk our students through an elaborate sequence 91 00:04:49,743 --> 00:04:53,480 of projects in which they gradually build a chip set, 92 00:04:53,480 --> 00:04:57,592 a hardware platform, an assembler, a virtual machine, 93 00:04:57,592 --> 00:05:01,169 a basic operating system and a compiler 94 00:05:01,169 --> 00:05:07,358 for a simple, Java-like language that we call "JACK." 95 00:05:07,358 --> 00:05:09,906 The students celebrate the end of this tour de force 96 00:05:09,906 --> 00:05:12,740 by using JACK to write all sorts of cool games 97 00:05:12,740 --> 00:05:15,732 like Pong, Snake and Tetris. 98 00:05:15,732 --> 00:05:19,347 You can imagine the tremendous joy of playing 99 00:05:19,347 --> 00:05:22,371 with a Tetris game that you wrote in JACK 100 00:05:22,371 --> 00:05:25,161 and then compiled into machine language in a compiler 101 00:05:25,161 --> 00:05:27,569 that you wrote also, and then seeing the result 102 00:05:27,569 --> 00:05:30,452 running on a machine that you built starting 103 00:05:30,452 --> 00:05:33,736 with nothing more than a few thousand NAND gates. 104 00:05:33,736 --> 00:05:36,926 It's a tremendous personal triumph of going 105 00:05:36,926 --> 00:05:41,651 from first principles all the way to a fantastically complex 106 00:05:41,651 --> 00:05:44,002 and useful system. 107 00:05:44,002 --> 00:05:48,399 Noam and I worked five years to facilitate 108 00:05:48,399 --> 00:05:51,607 this ascent and to create the tools and infrastructure 109 00:05:51,607 --> 00:05:54,780 that will enable students to build it in one semester. 110 00:05:54,780 --> 00:05:58,819 And this is the great team that helped us make it happen. 111 00:05:58,819 --> 00:06:03,066 The trick was to decompose the computer's construction 112 00:06:03,066 --> 00:06:06,020 into numerous stand-alone modules, 113 00:06:06,020 --> 00:06:09,920 each of which could be individually specified, 114 00:06:09,920 --> 00:06:15,155 built and unit-tested in isolation from the rest of the project. 115 00:06:15,155 --> 00:06:18,144 And from day one, Noam and I decided to put 116 00:06:18,144 --> 00:06:21,680 all these building blocks freely available in open source 117 00:06:21,680 --> 00:06:23,160 on the Web. 118 00:06:23,160 --> 00:06:27,631 So chip specifications, APIs, project descriptions, 119 00:06:27,631 --> 00:06:31,535 software tools, hardware simulators, CPU emulators, 120 00:06:31,535 --> 00:06:35,237 stacks of hundreds of slides, lectures -- 121 00:06:35,237 --> 00:06:37,464 we laid out everything on the Web 122 00:06:37,464 --> 00:06:40,491 and invited the world to come over, 123 00:06:40,491 --> 00:06:42,027 take whatever they need, 124 00:06:42,027 --> 00:06:44,417 and do whatever they want with it. 125 00:06:44,417 --> 00:06:48,316 And then something fascinating happened. 126 00:06:48,316 --> 00:06:49,899 The world came. 127 00:06:49,899 --> 00:06:53,057 And in short order, thousands of people 128 00:06:53,057 --> 00:06:54,601 were building our machine. 129 00:06:54,601 --> 00:06:58,525 And NAND2Tetris became one of the first 130 00:06:58,525 --> 00:07:01,755 massive, open, online courses, 131 00:07:01,755 --> 00:07:04,499 although seven years ago we had no idea that what 132 00:07:04,499 --> 00:07:06,660 we were doing is called MOOCs. 133 00:07:06,660 --> 00:07:10,518 We just observed how self-organized courses 134 00:07:10,518 --> 00:07:13,600 were kind of spontaneously spawning 135 00:07:13,600 --> 00:07:14,983 out of our materials. 136 00:07:14,983 --> 00:07:18,074 For example, Pramode C.E., 137 00:07:18,074 --> 00:07:19,983 an engineer from Kerala, India, 138 00:07:19,983 --> 00:07:21,792 has organized groups of self-learners 139 00:07:21,792 --> 00:07:24,836 who build our computer under his good guidance. 140 00:07:24,836 --> 00:07:27,858 And Parag Shah, another engineer, from Mumbai, 141 00:07:27,858 --> 00:07:30,703 has unbundled our projects into smaller, 142 00:07:30,703 --> 00:07:32,725 more manageable bites that he now serves 143 00:07:32,725 --> 00:07:36,527 in his pioneering do-it-yourself computer science program. 144 00:07:36,527 --> 00:07:39,938 The people who are attracted to these courses 145 00:07:39,938 --> 00:07:42,358 typically have a hacker mentality. 146 00:07:42,358 --> 00:07:44,463 They want to figure out how things work, 147 00:07:44,463 --> 00:07:46,223 and they want to do it in groups, 148 00:07:46,223 --> 00:07:49,034 like this hackers club in Washington, D.C., 149 00:07:49,034 --> 00:07:52,699 that uses our materials to offer community courses. 150 00:07:52,699 --> 00:07:55,645 And because these materials are widely available 151 00:07:55,645 --> 00:07:58,339 and open-source, different people take them 152 00:07:58,339 --> 00:08:01,282 to very different and unpredictable directions. 153 00:08:01,282 --> 00:08:04,195 For example, Yu Fangmin, from Guangzhou, 154 00:08:04,195 --> 00:08:07,041 has used FPGA technology 155 00:08:07,041 --> 00:08:10,766 to build our computer and show others how to do the same 156 00:08:10,766 --> 00:08:14,129 using a video clip, and Ben Craddock developed 157 00:08:14,129 --> 00:08:17,730 a very nice computer game that unfolds 158 00:08:17,730 --> 00:08:22,699 inside our CPU architecture, which is quite a complex 159 00:08:22,699 --> 00:08:25,184 3D maze that Ben developed 160 00:08:25,184 --> 00:08:29,092 using the Minecraft 3D simulator engine. 161 00:08:29,092 --> 00:08:32,110 The Minecraft community went bananas over this project, 162 00:08:32,110 --> 00:08:35,494 and Ben became an instant media celebrity. 163 00:08:35,494 --> 00:08:38,396 And indeed, for quite a few people, 164 00:08:38,396 --> 00:08:42,473 taking this NAND2Tetris pilgrimage, if you will, 165 00:08:42,473 --> 00:08:45,185 has turned into a life-changing experience. 166 00:08:45,185 --> 00:08:48,374 For example, take Dan Rounds, who is a music 167 00:08:48,374 --> 00:08:51,143 and math major from East Lansing, Michigan. 168 00:08:51,143 --> 00:08:54,587 A few weeks ago, Dan posted a victorious post 169 00:08:54,587 --> 00:08:57,207 on our website, and I'd like to read it to you. 170 00:08:57,207 --> 00:09:00,665 So here's what Dan said. 171 00:09:00,665 --> 00:09:03,477 "I did the coursework because understanding computers 172 00:09:03,477 --> 00:09:06,823 is important to me, just like literacy and numeracy, 173 00:09:06,823 --> 00:09:09,840 and I made it through. I never worked harder on anything, 174 00:09:09,840 --> 00:09:12,549 never been challenged to this degree. 175 00:09:12,549 --> 00:09:14,936 But given what I now feel capable of doing, 176 00:09:14,936 --> 00:09:17,094 I would certainly do it again. 177 00:09:17,094 --> 00:09:19,344 To anyone considering NAND2Tetris, 178 00:09:19,344 --> 00:09:23,090 it's a tough journey, but you'll be profoundly changed." 179 00:09:23,090 --> 00:09:27,990 So Dan demonstrates the many self-learners 180 00:09:27,990 --> 00:09:32,636 who take this course off the Web, on their own traction, 181 00:09:32,636 --> 00:09:37,225 on their own initiative, and it's quite amazing because 182 00:09:37,225 --> 00:09:41,812 these people cannot care less about 183 00:09:41,812 --> 00:09:43,054 grades. 184 00:09:43,054 --> 00:09:46,959 They are doing it because of one motivation only. 185 00:09:46,959 --> 00:09:50,445 They have a tremendous passion to learn. 186 00:09:50,445 --> 00:09:52,369 And with that in mind, 187 00:09:52,369 --> 00:09:56,973 I'd like to say a few words about traditional college grading. 188 00:09:56,973 --> 00:09:59,333 I'm sick of it. 189 00:09:59,333 --> 00:10:00,766 We are obsessed with grades 190 00:10:00,766 --> 00:10:02,632 because we are obsessed with data, 191 00:10:02,632 --> 00:10:07,219 and yet grading takes away all the fun from failing, 192 00:10:07,219 --> 00:10:09,695 and a huge part of education 193 00:10:09,695 --> 00:10:11,286 is about failing. 194 00:10:11,286 --> 00:10:13,761 Courage, according to Churchill, 195 00:10:13,761 --> 00:10:16,707 is the ability to go from one defeat to another 196 00:10:16,707 --> 00:10:19,321 without losing enthusiasm. (Laughter) 197 00:10:19,321 --> 00:10:23,151 And [Joyce] said that mistakes 198 00:10:23,151 --> 00:10:24,620 are the portals of discovery. 199 00:10:24,620 --> 00:10:27,966 And yet we don't tolerate mistakes, 200 00:10:27,966 --> 00:10:29,275 and we worship grades. 201 00:10:29,275 --> 00:10:33,063 So we collect your B pluses and your A minuses 202 00:10:33,063 --> 00:10:35,900 and we aggregate them into a number like 3.4, 203 00:10:35,900 --> 00:10:37,811 which is stamped on your forehead 204 00:10:37,811 --> 00:10:40,254 and sums up who you are. 205 00:10:40,254 --> 00:10:43,537 Well, in my opinion, we went too far with this nonsense, 206 00:10:43,537 --> 00:10:46,218 and grading became degrading. 207 00:10:46,218 --> 00:10:51,119 So with that, I'd like to say a few words about upgrading, 208 00:10:51,119 --> 00:10:55,544 and share with you a glimpse from my current project, 209 00:10:55,544 --> 00:10:57,574 which is different from the previous one, 210 00:10:57,574 --> 00:10:59,588 but it shares exactly the same characteristics 211 00:10:59,588 --> 00:11:03,415 of self-learning, learning by doing, 212 00:11:03,415 --> 00:11:06,190 self-exploration and community-building, 213 00:11:06,190 --> 00:11:12,050 and this project deals with K-12 math education, 214 00:11:12,050 --> 00:11:13,954 beginning with early age math, 215 00:11:13,954 --> 00:11:18,447 and we do it on tablets because we believe that 216 00:11:18,447 --> 00:11:22,852 math, like anything else, should be taught hands on. 217 00:11:22,852 --> 00:11:26,007 So here's what we do. Basically, we developed 218 00:11:26,007 --> 00:11:29,765 numerous mobile apps, every one of them explaining 219 00:11:29,765 --> 00:11:31,262 a particular concept in math. 220 00:11:31,262 --> 00:11:34,703 So for example, let's take area. 221 00:11:34,703 --> 00:11:37,175 When you deal with a concept like area -- 222 00:11:37,175 --> 00:11:42,419 well, we also provide a set of tools that the child 223 00:11:42,419 --> 00:11:45,050 is invited to experiment with in order to learn. 224 00:11:45,050 --> 00:11:49,003 So if area is what interests us, then one thing 225 00:11:49,003 --> 00:11:53,141 which is natural to do is to tile the area 226 00:11:53,141 --> 00:11:56,791 of this particular shape and simply count 227 00:11:56,791 --> 00:12:00,654 how many tiles it takes to cover it completely. 228 00:12:00,654 --> 00:12:03,136 And this little exercise here gives you a first 229 00:12:03,136 --> 00:12:06,565 good insight of the notion of area. 230 00:12:06,565 --> 00:12:09,355 Moving along, what about the area of this figure? 231 00:12:09,355 --> 00:12:14,012 Well, if you try to tile it, it doesn't work too well, does it. 232 00:12:14,012 --> 00:12:16,316 So instead, you can experiment 233 00:12:16,316 --> 00:12:18,996 with these different tools here by some process 234 00:12:18,996 --> 00:12:21,035 of guided trial and error, 235 00:12:21,035 --> 00:12:23,873 and at some point you will discover that one thing 236 00:12:23,873 --> 00:12:26,961 that you can do among several legitimate transformations 237 00:12:26,961 --> 00:12:29,792 is the following one. You can cut the figure, 238 00:12:29,792 --> 00:12:33,408 you can rearrange the parts, you can glue them 239 00:12:33,408 --> 00:12:36,525 and then proceed to tile just like we did before. 240 00:12:36,525 --> 00:12:41,800 (Applause) 241 00:12:41,800 --> 00:12:44,523 Now this particular transformation 242 00:12:44,523 --> 00:12:48,507 did not change the area of the original figure, 243 00:12:48,507 --> 00:12:50,694 so a six-year-old who plays with this 244 00:12:50,694 --> 00:12:53,578 has just discovered a clever algorithm 245 00:12:53,578 --> 00:12:57,618 to compute the area of any given parallelogram. 246 00:12:57,618 --> 00:12:59,474 We don't replace teachers, by the way. 247 00:12:59,474 --> 00:13:02,603 We believe that teachers should be empowered, not replaced. 248 00:13:02,603 --> 00:13:05,898 Moving along, what about the area of a triangle? 249 00:13:05,898 --> 00:13:08,693 So after some guided trial and error, 250 00:13:08,693 --> 00:13:12,628 the child will discover, with or without help, 251 00:13:12,628 --> 00:13:16,486 that he or she can duplicate the original figure 252 00:13:16,486 --> 00:13:19,894 and then take the result, transpose it, 253 00:13:19,894 --> 00:13:23,642 glue it to the original and then proceed [with] what we did before: 254 00:13:23,642 --> 00:13:31,370 cut, rearrange, paste — oops— paste and glue, 255 00:13:31,370 --> 00:13:32,966 and tile. 256 00:13:32,966 --> 00:13:36,793 Now this transformation has doubled the area 257 00:13:36,793 --> 00:13:40,643 of the original figure, and therefore we have just learned 258 00:13:40,643 --> 00:13:44,409 that the area of the triangle equals the area of this rectangle 259 00:13:44,409 --> 00:13:46,863 divided by two. 260 00:13:46,863 --> 00:13:50,311 But we discovered it by self-exploration. 261 00:13:50,311 --> 00:13:56,391 So, in addition to learning some useful geometry, 262 00:13:56,391 --> 00:14:00,778 the child has been exposed to some pretty sophisticated 263 00:14:00,778 --> 00:14:03,805 science strategies, like reduction, 264 00:14:03,805 --> 00:14:06,719 which is the art of 265 00:14:06,719 --> 00:14:10,305 transforming a complex problem into a simple one, 266 00:14:10,305 --> 00:14:12,674 or generalization, which is at the heart 267 00:14:12,674 --> 00:14:15,517 of any scientific discipline, 268 00:14:15,517 --> 00:14:18,107 or the fact that some properties are invariant 269 00:14:18,107 --> 00:14:21,131 under some transformations. 270 00:14:21,131 --> 00:14:24,416 And all this is something that a very young child 271 00:14:24,416 --> 00:14:28,725 can pick up using such mobile apps. 272 00:14:28,725 --> 00:14:31,819 So presently, we are doing the following: 273 00:14:31,819 --> 00:14:36,128 First of all, we are decomposing the K-12 math curriculum 274 00:14:36,128 --> 00:14:39,019 into numerous such apps. 275 00:14:39,019 --> 00:14:41,596 And because we cannot do it on our own, 276 00:14:41,596 --> 00:14:44,690 we've developed a very fancy authoring tool 277 00:14:44,690 --> 00:14:47,965 that any author, any parent or actually anyone 278 00:14:47,965 --> 00:14:50,318 who has an interest in math education, 279 00:14:50,318 --> 00:14:53,590 can use this authoring tool to develop similar apps 280 00:14:53,590 --> 00:14:56,995 on tablets without programming. 281 00:14:56,995 --> 00:15:00,215 And finally, we are putting together an adaptive ecosystem 282 00:15:00,215 --> 00:15:03,043 that will match different learners 283 00:15:03,043 --> 00:15:08,420 with different apps according to their evolving learning style. 284 00:15:08,420 --> 00:15:10,941 The driving force behind this project 285 00:15:10,941 --> 00:15:13,888 is my colleague Shmulik London, 286 00:15:13,888 --> 00:15:16,532 and, you see, just like 287 00:15:16,532 --> 00:15:20,605 Salman did about 90 years ago, 288 00:15:20,605 --> 00:15:24,576 the trick is to surround yourself with brilliant people, 289 00:15:24,576 --> 00:15:27,332 because at the end, 290 00:15:27,332 --> 00:15:29,235 it's all about people. 291 00:15:29,235 --> 00:15:32,654 And a few years ago, I was walking in Tel Aviv 292 00:15:32,654 --> 00:15:35,484 and I saw this graffiti on a wall, 293 00:15:35,484 --> 00:15:37,275 and I found it so compelling 294 00:15:37,275 --> 00:15:39,418 that by now I preach it to my students, 295 00:15:39,418 --> 00:15:41,684 and I'd like to try to preach it to you. 296 00:15:41,684 --> 00:15:43,424 Now, I don't know how many people here are familiar 297 00:15:43,424 --> 00:15:45,252 with the term "mensch." 298 00:15:45,252 --> 00:15:47,860 It basically means to be human 299 00:15:47,860 --> 00:15:49,795 and to do the right thing. 300 00:15:49,795 --> 00:15:52,224 And with that, what this graffiti says is, 301 00:15:52,224 --> 00:15:54,310 "High-tech schmigh-tech. 302 00:15:54,310 --> 00:15:56,873 The most important thing is to be a mensch." (Laughter) 303 00:15:56,873 --> 00:16:00,268 Thank you. (Applause) 304 00:16:00,268 --> 00:16:05,051 (Applause)