WEBVTT 00:00:00.434 --> 00:00:01.850 What I want to do in this video is 00:00:01.850 --> 00:00:04.690 think about the origins of algebra. 00:00:04.690 --> 00:00:08.390 The origins of algebra, and the word, 00:00:08.390 --> 00:00:10.640 especially in association with the ideas 00:00:10.640 --> 00:00:15.617 that algebra now represents, comes from this book, 00:00:15.617 --> 00:00:17.950 or actually this is a page of the book right over there. 00:00:17.950 --> 00:00:20.430 The English translation for the title of this book 00:00:20.430 --> 00:00:23.050 is the "Compendious Book on Calculation 00:00:23.050 --> 00:00:25.280 by Completion and Balancing." 00:00:25.280 --> 00:00:29.120 And it was written by a Persian mathematician who 00:00:29.120 --> 00:00:32.052 lived in Baghdad in, I believe, it 00:00:32.052 --> 00:00:33.510 was in the eighth or ninth century. 00:00:33.510 --> 00:00:37.740 I believe it was actually 820 AD when he wrote this book. 00:00:37.740 --> 00:00:38.620 AD. 00:00:38.620 --> 00:00:42.730 And algebra is the Arabic word, that here is the actual title 00:00:42.730 --> 00:00:45.070 that he gave to it, which is the Arabic title. 00:00:45.070 --> 00:00:47.456 Algebra means restoration or completion. 00:00:50.600 --> 00:00:55.110 Restoration or completion. 00:00:55.110 --> 00:00:58.380 And he associated it in his book with a very specific operation, 00:00:58.380 --> 00:01:01.490 really taking something from one side of an equation 00:01:01.490 --> 00:01:03.659 to another side of an equation. 00:01:03.659 --> 00:01:05.450 But we can actually see it right over here, 00:01:05.450 --> 00:01:07.075 and I don't know Arabic, but I actually 00:01:07.075 --> 00:01:08.550 do know some languages that seems 00:01:08.550 --> 00:01:10.330 to have borrowed a little bit from Arabic, 00:01:10.330 --> 00:01:12.310 or maybe it went the other way around. 00:01:12.310 --> 00:01:15.770 But this says Al-kitab, and I know just enough 00:01:15.770 --> 00:01:18.350 Urdu and Hindi to understand a good India movie, 00:01:18.350 --> 00:01:20.170 but Al-kitab, kitab means book. 00:01:20.170 --> 00:01:22.550 So this part is book. 00:01:22.550 --> 00:01:23.170 Book. 00:01:23.170 --> 00:01:26.816 Al-mukhtasar, well, I think that means compendious, 00:01:26.816 --> 00:01:28.690 because I don't know the word for compendious 00:01:28.690 --> 00:01:29.930 and that seems like that. 00:01:29.930 --> 00:01:33.170 Fihisab, hisab means calculation in Hindi or Urdu, 00:01:33.170 --> 00:01:35.210 so this is calculation. 00:01:35.210 --> 00:01:36.300 Calculation. 00:01:36.300 --> 00:01:38.500 Al-gabr, this is the root. 00:01:38.500 --> 00:01:41.110 This is the famous algebra, this is where it shows up. 00:01:41.110 --> 00:01:45.520 So this is for completion, you could view that as completion. 00:01:45.520 --> 00:01:46.450 Completion. 00:01:46.450 --> 00:01:52.050 And then wa'l-muqabala, and that means essentially balancing. 00:01:52.050 --> 00:01:52.660 Balancing. 00:01:52.660 --> 00:01:55.305 Completion and balancing. 00:01:55.305 --> 00:01:56.680 So if we wanted to translate it-- 00:01:56.680 --> 00:01:58.890 I know this isn't a video on translating Arabic, 00:01:58.890 --> 00:02:04.100 but the book, I guess this is saying compendious 00:02:04.100 --> 00:02:10.720 on calculation by completion and balancing 00:02:10.720 --> 00:02:12.580 is the rough translation right over there. 00:02:12.580 --> 00:02:15.470 But that is the source of the word algebra, 00:02:15.470 --> 00:02:17.940 and this is a very, very, very important book. 00:02:17.940 --> 00:02:20.700 Not just because it was the first use of the word algebra, 00:02:20.700 --> 00:02:24.720 but many people viewed this book as the first time 00:02:24.720 --> 00:02:29.800 that algebra took a lot of its modern-- 00:02:29.800 --> 00:02:31.940 took on many of its modern ideas. 00:02:31.940 --> 00:02:34.240 Ideas of balancing an equation. 00:02:34.240 --> 00:02:36.320 The abstract problem itself, not trying 00:02:36.320 --> 00:02:38.540 to do one off problems here or there. 00:02:38.540 --> 00:02:42.160 But al-Khwarizmi was not the first person, 00:02:42.160 --> 00:02:44.640 and just to get an idea of where all this is happening. 00:02:44.640 --> 00:02:47.122 So he was hanging out in Baghdad, 00:02:47.122 --> 00:02:48.580 and this part of the world shows up 00:02:48.580 --> 00:02:50.130 a lot in the history of algebra. 00:02:50.130 --> 00:02:51.650 But he was hanging out right there 00:02:51.650 --> 00:02:54.050 in around the eighth or ninth century. 00:02:54.050 --> 00:02:56.150 So let me draw a time line here, just 00:02:56.150 --> 00:02:58.230 so we can appreciate everything. 00:02:58.230 --> 00:03:03.590 So that is timeline, and then whether or not 00:03:03.590 --> 00:03:06.710 you are religious, most of our modern dates 00:03:06.710 --> 00:03:11.720 are dependent on the birth of Jesus, so that is right there. 00:03:11.720 --> 00:03:13.905 Maybe I'll put a cross over there to signify that. 00:03:13.905 --> 00:03:15.280 When we want to be non-religious, 00:03:15.280 --> 00:03:17.110 we say the common era. 00:03:17.110 --> 00:03:19.750 Before the common era, when we want to be religious 00:03:19.750 --> 00:03:22.530 we say AD, which means in the year of our lord. 00:03:22.530 --> 00:03:25.120 I don't know the Latin, Anno Domini, I believe, 00:03:25.120 --> 00:03:26.220 year of our lord. 00:03:26.220 --> 00:03:28.970 And then when we want-- in the religious context, 00:03:28.970 --> 00:03:32.180 instead of saying before common era, we say before Christ, BC. 00:03:32.180 --> 00:03:36.790 But either way, so this is 1000 in the common era. 00:03:36.790 --> 00:03:39.656 This is 2000 in the common era. 00:03:39.656 --> 00:03:41.530 And obviously, we are sitting-- at least when 00:03:41.530 --> 00:03:44.400 I'm making this video, I'm sitting right about there. 00:03:44.400 --> 00:03:48.560 And then this is 1000 before the common era, 00:03:48.560 --> 00:03:52.210 and this is 2000 before the common era. 00:03:52.210 --> 00:03:54.565 So the first traces-- and I'm skipping out, 00:03:54.565 --> 00:03:56.190 and really, it's just what we can find. 00:03:56.190 --> 00:03:57.420 I'm sure if we were able to dig more, 00:03:57.420 --> 00:03:59.044 we might be able to find other evidence 00:03:59.044 --> 00:04:02.080 of different civilizations and different people stumbling 00:04:02.080 --> 00:04:04.720 on many of the ideas in algebra. 00:04:04.720 --> 00:04:07.430 But our first records of people really exploring 00:04:07.430 --> 00:04:09.690 the ideas that are hit upon in algebra 00:04:09.690 --> 00:04:13.590 come from ancient Babylon around 2000 years 00:04:13.590 --> 00:04:16.160 before the common era, before Christ. 00:04:16.160 --> 00:04:22.562 So right around there there are stone tablets 00:04:22.562 --> 00:04:24.270 where it looks like people were exploring 00:04:24.270 --> 00:04:26.080 some of the fundamental ideas of algebra. 00:04:26.080 --> 00:04:27.880 They weren't using the same symbols. 00:04:27.880 --> 00:04:30.780 They weren't using the same ways of representing the numbers, 00:04:30.780 --> 00:04:33.090 but it was algebra that they were working on. 00:04:33.090 --> 00:04:35.430 And that was, once again, in this part of the world. 00:04:35.430 --> 00:04:38.760 Babylon was right about there. 00:04:38.760 --> 00:04:42.720 And Babylon, it's kind of kept the tradition of Sumeria. 00:04:42.720 --> 00:04:44.920 This whole region was called Mesopotamia, 00:04:44.920 --> 00:04:47.290 Greek for between two rivers. 00:04:47.290 --> 00:04:49.230 But that's the first traces of people 00:04:49.230 --> 00:04:51.270 that we know of that where people were starting 00:04:51.270 --> 00:04:54.550 to do what we would call real, real algebra. 00:04:54.550 --> 00:04:55.892 And then you fast forward. 00:04:55.892 --> 00:04:57.600 And I'm sure we're missing-- and I'm sure 00:04:57.600 --> 00:05:01.960 even our historians don't know all of the different instances 00:05:01.960 --> 00:05:08.300 of people using algebra, but the major contributions to algebra, 00:05:08.300 --> 00:05:11.450 we saw it here in Babylon 2000 years ago. 00:05:11.450 --> 00:05:13.990 And then if we fast forward to about 200 to 300 00:05:13.990 --> 00:05:17.310 AD, so right over there, you have a Greek gentleman 00:05:17.310 --> 00:05:18.870 who lived in Alexandria. 00:05:18.870 --> 00:05:21.020 So this is Greece right over here, 00:05:21.020 --> 00:05:23.210 but he lived in Alexandria, which at the time 00:05:23.210 --> 00:05:25.240 was part of the Roman Empire. 00:05:25.240 --> 00:05:27.890 So Alexandria is right over here, 00:05:27.890 --> 00:05:30.630 and he was a gentleman by the name of Diophantus, 00:05:30.630 --> 00:05:31.890 or Diophantus. 00:05:31.890 --> 00:05:36.300 I don't know how to pronounce it, Diophantus. 00:05:36.300 --> 00:05:38.550 And he is sometimes credited with being 00:05:38.550 --> 00:05:41.330 the father of algebra, and it's debatable 00:05:41.330 --> 00:05:44.200 whether it's Diophantus or al-Khwarizmi. 00:05:44.200 --> 00:05:45.770 al-Khwarizmi, who kind of started 00:05:45.770 --> 00:05:48.320 using these terms of balancing equations 00:05:48.320 --> 00:05:50.050 and talking about math in a purer way, 00:05:50.050 --> 00:05:53.370 while Diophantus was more focused on particular problems. 00:05:53.370 --> 00:05:55.840 And both of them were kind of beat to the punch 00:05:55.840 --> 00:05:57.780 by the Babylonians, although they all 00:05:57.780 --> 00:05:59.170 did contribute in their own way. 00:05:59.170 --> 00:06:00.140 It's not like they were just copying 00:06:00.140 --> 00:06:01.370 what the Babylonians did. 00:06:01.370 --> 00:06:03.230 They had their own unique contributions 00:06:03.230 --> 00:06:06.360 to what we now consider algebra. 00:06:06.360 --> 00:06:08.170 But many, especially Western historians, 00:06:08.170 --> 00:06:11.480 associate Diophantus as the father of algebra. 00:06:11.480 --> 00:06:13.580 And now, al-Khwarizmi is sometimes 00:06:13.580 --> 00:06:16.390 what other people would argue as the father of algebra, 00:06:16.390 --> 00:06:18.290 so he made significant contributions. 00:06:18.290 --> 00:06:22.200 And if you go to 600 AD-- so if you go to about 600 AD, 00:06:22.200 --> 00:06:26.140 another famous mathematician in the history of algebra 00:06:26.140 --> 00:06:29.200 was Brahmagupta, in India. 00:06:29.200 --> 00:06:32.580 Brahmagupta, in India. 00:06:32.580 --> 00:06:34.180 So obviously, and actually, I don't 00:06:34.180 --> 00:06:35.490 know where in India he lived. 00:06:35.490 --> 00:06:37.900 I should look that up, but roughly 00:06:37.900 --> 00:06:39.440 in that part of the world. 00:06:39.440 --> 00:06:41.665 And he also made significant contributions. 00:06:44.290 --> 00:06:45.790 And then you have al-Khwarizmi, who 00:06:45.790 --> 00:06:50.530 shows up right there, al-Khwarizmi. 00:06:50.530 --> 00:06:53.560 And he is the gentleman that definitely 00:06:53.560 --> 00:06:56.810 we credit with the name algebra, comes from Arabic 00:06:56.810 --> 00:07:00.080 for restoration, and some people also consider him to be, 00:07:00.080 --> 00:07:02.170 if not the father of algebra, although some people 00:07:02.170 --> 00:07:05.370 say he is the father, he is one of the fathers of algebra 00:07:05.370 --> 00:07:08.340 because he really started to think about algebra 00:07:08.340 --> 00:07:11.410 in the abstract sense, devoid of some specific problems 00:07:11.410 --> 00:07:13.440 and a lot of the way a modern mathematician 00:07:13.440 --> 00:07:17.110 would start to think about the field.