WEBVTT 00:00:15.526 --> 00:00:17.050 This image of the Vitruvian Man, 00:00:17.074 --> 00:00:18.302 taken from Leonardo's sketches, 00:00:18.326 --> 00:00:20.184 has become one of the most recognizable 00:00:20.208 --> 00:00:21.625 symbols of the Renaissance. 00:00:21.649 --> 00:00:22.719 But why? 00:00:22.743 --> 00:00:24.696 It's a simple pen and ink drawing, right? 00:00:24.720 --> 00:00:25.979 Wrong! 00:00:26.003 --> 00:00:27.373 Let's start to answer this question 00:00:27.397 --> 00:00:28.610 with a math problem. 00:00:28.634 --> 00:00:30.777 I know how to calculate the area of a circle. 00:00:30.801 --> 00:00:32.075 I take the value for pi 00:00:32.099 --> 00:00:34.323 and multiply it by the radius squared. 00:00:34.347 --> 00:00:36.541 I also know how to take the area of a square. 00:00:36.565 --> 00:00:39.340 I multiply the base by itself. 00:00:39.364 --> 00:00:41.384 But how can I take the area of a circle 00:00:41.408 --> 00:00:43.775 and create a square with an equal area? 00:00:43.799 --> 00:00:45.715 This is a problem often called "squaring a circle" 00:00:45.739 --> 00:00:48.023 that was first proposed in the ancient world. 00:00:48.047 --> 00:00:49.634 And like many of ideas of the ancient world, 00:00:49.658 --> 00:00:51.870 it was given new life during the Renaissance. 00:00:51.894 --> 00:00:53.054 As it turns out, 00:00:53.078 --> 00:00:54.442 this problem is impossible to solve 00:00:54.466 --> 00:00:56.066 because of the nature of pi, 00:00:56.090 --> 00:00:57.888 but that's another story. 00:00:57.912 --> 00:00:58.602 Leonardo's sketch, 00:00:58.626 --> 00:00:59.856 which is influenced by the writings 00:00:59.880 --> 00:01:01.881 of the Roman architect, Vitruvius, 00:01:01.905 --> 00:01:03.486 places a man firmly at the center 00:01:03.510 --> 00:01:05.483 of a circle and a square. 00:01:05.507 --> 00:01:06.818 Vitruvius claimed the navel 00:01:06.842 --> 00:01:08.079 is the center of the human body 00:01:08.103 --> 00:01:09.605 and that if one takes a compass 00:01:09.629 --> 00:01:11.534 and places the fixed point on the navel, 00:01:11.558 --> 00:01:13.991 a circle can be drawn perfectly around the body. 00:01:14.015 --> 00:01:15.980 Additionally, Vitruvius recognized 00:01:16.004 --> 00:01:17.082 that arm span and height 00:01:17.106 --> 00:01:19.726 have a nearly perfect correspondence in the human body, 00:01:19.750 --> 00:01:22.833 thus placing the body perfectly inside a square as well. 00:01:22.857 --> 00:01:24.207 Leonardo used the ideas of Vitruvius 00:01:24.231 --> 00:01:27.003 to solve the problem of squaring a circle metaphorically 00:01:27.027 --> 00:01:29.711 using mankind as the area for both shapes. 00:01:29.735 --> 00:01:32.587 Leonardo wasn't just thinking about Vitruvius, though. 00:01:32.611 --> 00:01:33.791 There was an intellectual movement 00:01:33.815 --> 00:01:34.889 in Italy at the time 00:01:34.913 --> 00:01:36.297 called Neoplatonism. 00:01:36.321 --> 00:01:37.717 This movement took an old concept 00:01:37.741 --> 00:01:40.421 from the 4th century developed by Plato and Aristotle, 00:01:40.445 --> 00:01:42.254 called "The Great Chain of Being". 00:01:42.278 --> 00:01:44.659 This belief holds that the universe is a hierarchy 00:01:44.683 --> 00:01:45.590 resembling a chain, 00:01:45.614 --> 00:01:47.755 and that chain starts at the top with God, 00:01:47.779 --> 00:01:49.712 then travels down through the angels, 00:01:49.736 --> 00:01:50.289 planets, 00:01:50.313 --> 00:01:50.878 stars, 00:01:50.902 --> 00:01:51.958 and all lifeforms 00:01:51.982 --> 00:01:54.042 before ending with demons and devils. 00:01:54.066 --> 00:01:55.789 Early in this philosophic movement, 00:01:55.813 --> 00:01:58.147 it was thought that mankind's place in this chain 00:01:58.171 --> 00:01:59.503 was exactly in the center. 00:01:59.527 --> 00:02:01.202 Because humans have a mortal body 00:02:01.226 --> 00:02:03.134 accompanied by an immortal soul, 00:02:03.158 --> 00:02:05.284 we divide the universe nicely in half. 00:02:05.308 --> 00:02:07.043 Around the time Leonardo sketched 00:02:07.067 --> 00:02:08.662 the Vitruvian Man, however, 00:02:08.686 --> 00:02:10.847 a Neoplatonist named Pico della Mirandola 00:02:10.871 --> 00:02:12.212 had a different idea. 00:02:12.236 --> 00:02:13.790 He pried mankind off the chain 00:02:13.814 --> 00:02:15.957 and claimed that humans have a unique ability 00:02:15.981 --> 00:02:17.621 to take any position they want. 00:02:17.645 --> 00:02:19.204 Pico claimed that God desired 00:02:19.228 --> 00:02:20.752 a being capable of comprehending 00:02:20.776 --> 00:02:23.545 the beautiful and complicated universe he had created. 00:02:23.569 --> 00:02:25.464 This led to the creation of mankind, 00:02:25.488 --> 00:02:27.584 which he placed at the center of the universe 00:02:27.608 --> 00:02:30.018 with the ability to take whatever form he pleases. 00:02:30.042 --> 00:02:32.117 Mankind, according to Pico, 00:02:32.141 --> 00:02:34.678 could crawl down the chain and behave like an animal 00:02:34.702 --> 00:02:36.899 or crawl up the chain and behave like a god, 00:02:36.923 --> 00:02:38.204 it's our choice. 00:02:38.228 --> 00:02:39.457 Looking back at the sketch, 00:02:39.481 --> 00:02:41.567 we can see that by changing the position of the man, 00:02:41.591 --> 00:02:43.306 he can fill the irreconcilable areas 00:02:43.330 --> 00:02:44.986 of a circle and a square. 00:02:45.010 --> 00:02:47.289 If geometry is the language the universe is written in, 00:02:47.313 --> 00:02:48.694 then this sketch seems to say 00:02:48.718 --> 00:02:50.493 we can exist within all its elements. 00:02:50.517 --> 00:02:52.034 Mankind can fill whatever shape 00:02:52.058 --> 00:02:53.329 he pleases geometrically 00:02:53.353 --> 00:02:55.248 and philosophically as well. 00:02:55.272 --> 00:02:56.328 In this one sketch, 00:02:56.352 --> 00:02:57.618 Leondardo was able to combine 00:02:57.642 --> 00:02:58.424 the mathematics, 00:02:58.448 --> 00:02:59.106 religion, 00:02:59.130 --> 00:02:59.920 philosophy, 00:02:59.944 --> 00:03:00.780 architecture, 00:03:00.804 --> 00:03:02.503 and artistic skill of his age. 00:03:02.527 --> 00:03:04.242 No wonder it has become such an icon 00:03:04.266 --> 00:03:06.278 for the entire time period.