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Current time:0:00Total duration:4:20

Video transcript

Voiceover:Hello and welcome to that one day of the year when, well, everyone else is building up how great Pi is. I'm here to tear it down, because you deserve the truth. Forget about the part where Pi isn't the correct circle concept. This Pi day, I'm not about how people worship Pi for being infinite for going on forever. First of all, Pi is not infinite. It is more three, but you know, less than four. There are cultures where three is the biggest number, so I don't want to be insensitive, but trust me on this four is not infinite and neither is Pi. I know it's not about it's magnitude, it's about all those digits, infinite digits going on forever, but first of all it doesn't go anywhere. It just is. There's no time element. If you had a number line, Pi would be exactly one point on that number line sitting perfect still right now. It's not going to start wondering off on an infinite journey that takes forever, or even on a finite journey that takes forever, or an infinite journey that takes finite time. Pi is a number not a process. Secondly, yeah, so it's got infinite digits. So what, one-third has infinite digits. There's exactly as exactly as many digits in one-third and in Pi as in 99.9999 repeating. Oh, and there's also as many digits as in numbers like, say, five, I know, big number. It's even more than four, so, it's piratically like double infinity. Which, it actuality kind of is, because in decimal innovation there's secretly infinite zeros in all of these places. Zero's going out to forever. Ooh! So mysterious, and then zero's going the other way too. Which is actually not any more zeros than if they only went one way. No. Pi is not especially infinite in any way, it's more like in-between-finite. There's an infinite number of rational numbers. for any two factions you can find another fraction that's between them again and again and again. There's never any fractions that are right next to each other on the number line. But, despite there's a infinite amount of rational numbers, Pi isn't one of them. Take any rational number, and you can find an infinite number of rational numbers that are closer to Pi on either side. Pi is between all of them in one of the gaps. It isn't infinite. It's in-between-finite. So what, you think that's special, as if there's just one hole in the rational number line exactly where Pi is, and once you plug that in with a super special number, you're good to go? Maybe, a few more for E and [towel] and square root too. No! Super nope! The in-between-[finiteness] of Pi, its irrationality is an incredibility un-special property. Turns out, most real numbers are irrational. It's the nicely packaged rational numbers that are weird. In fact, if you threw a dart and picked a random number off the number line, the chance of getting a rational number is exactly zero. I'll get into kinds of infinities some other time, but [unintelligible] to say the number of rational numbers, like the number of digits in Pi, is the small and unimpressive countable infinity. While the number of irrational numbers is so much bigger than countable infinity, that when you compare the two, cantabile infinity looks like zero. So, I don't know why anyone would make a fus about the grand infinities and forever, as about the boring little number like Pi. And of course, those are just the first couple of kinds of infinities in an infinite number of infinities in their correspondingly more in-between-[finiter] numbers like the [infinitesimals]. So, don't let Pi impress you by being a member of an unaccountably infinite set of in-between-infinite number either. The only thing even a little weird about Pi is that you do get an irrational number by taking such a simple ratio of such a simple geometric object. Surely that never happens with other simple ratios of other simple geometric objects. Oh wait! Their in everything! What are the chances? No! Let's pretend math equals arithmetic, and then get all surprised and amazed when the moment you leave arithmetic that you get a non-arithmetic number as if it were some odd unpredictable phenomenon. That way, by the time you get to calculus you won't have any idea what's going on and memorize just enough symbol shuffling to pass your class without ever realizing that you were dealing with infinities two levels deeper than the infinity you think is so cool when Pi does it. Pi is not special. Yeah, Pi can be fun, and I'd never deny you your deserts, but maybe try some real food once in a while.