Recently, pi has been under “attack” by a new constant called tau. You can read about it here:
- The original article
Ï€ is wrong written by Bob Palais (published in 2000/2001). - The Tau Manifesto written by Michael Hartl (launched on June 28th, 2010).
- The video Pi is (still) wrong by Vi Hart (uploaded on March 14th, 2011).
I find tau to be quite interesting, but alas, someone has to defend pi.
Check out the Pi Manifesto on why pi really is the true circle constant!

If someone as hot as Vi Hart says pi is wrong, I’m listening. 😀
Hmm, we’ll have to see what side BrownSharpie is on…
Is that picture yours?
About Tau: To me tau is the same as using pi
Tau = pi – a leg
lol
The picture in the comments? That’s just a random picture I found…
In my opinion, the “real” reason to change from pi to tau is solely for those new to math. Using tau when learning about all of this non intuitive “crap” (as I thought when while still in school) actually does make it easier. For anyone who already do know how to use pi and tau, there is a free choice of which to use (and if one need to choose one should be skilled enough to be able to do so). Refusing to change ones point of view of the world, where a change would make it easier for coming generations, only means that one is a silly, grumpy old geezer. Or as a geezer might say: “this new music sucks, it was much better in my days when……” oh sorry – it was math this time: “this new math sucks, ofc the kids will learn pi. I did; and back in my days we had to walk miles through the woods to get to the school, fighting the wildlife as we walked”.
I honestly think that the whole argumentation around pi and tau only cements what I learned in grad school – academic research is just a gargantuan sandbox in which most of the people behave like kids that argue over petty viewpoints instead of cooperating and making the world a better place (and by that, I’m _not_ stating that industrial research is any different or better).
Sorry for posting this here and not on the forum – I wanted to rant a little but couldnt be bothered about making an account
Totally agree 😀