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## About pi and tau

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

# Anti-Pi Rant, 3/14/14

## 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.