### Happy Pi Day!!

Today, as every geek worthy of the name knows, is Pi Day. For those of you who have a life, it is called that because the date is 3/14, resembling the constant pi to 2 digits.

Pi is probably America's most beloved transcendental number, but there are some who want to knock it from it's perch. In his Tau Manifesto, Michael Hartl makes arguments for making tau, or twice pi, the "circle constant".

He makes some good arguments. But there are a couple of questions he doesn't answer very well. Changing the textbooks will not be as simple a matter as he makes it out to be. Consider how persistent Leibniz's notation for calculus has been. And it's not because no one has challenged it. I have a friend who wrote a textbook back in the 70's using a completely different notation. It went nowhere.

Leibniz developed his notation in the 18th century. Pi was first proposed (although not with that name) by Archimedes over 2000 years ago. That's a lot that would have to be changed.

Hartl's weakest argument is about puns. (Although that's admittedly the least important argument...I am really praising him with faint damnation here.) The new puns he proposes are based on pronouncing "tau" like "tao". No. Tau rhymes with saw.Tao rhymes with dow. They aren't homonyms like "pi" and "pie".

There is no substitute for the old pi puns. One thing that makes them especially delightful is that pie is round. A pie is a circle, and pi describes a circle. You can't come up with anything that beautiful with tau.

There are no pastries that sound like tau. There is nothing we have an excuse to eat on tau day.

Now if you will excuse me, I am going to go have some pie.

Pi is probably America's most beloved transcendental number, but there are some who want to knock it from it's perch. In his Tau Manifesto, Michael Hartl makes arguments for making tau, or twice pi, the "circle constant".

He makes some good arguments. But there are a couple of questions he doesn't answer very well. Changing the textbooks will not be as simple a matter as he makes it out to be. Consider how persistent Leibniz's notation for calculus has been. And it's not because no one has challenged it. I have a friend who wrote a textbook back in the 70's using a completely different notation. It went nowhere.

Leibniz developed his notation in the 18th century. Pi was first proposed (although not with that name) by Archimedes over 2000 years ago. That's a lot that would have to be changed.

Hartl's weakest argument is about puns. (Although that's admittedly the least important argument...I am really praising him with faint damnation here.) The new puns he proposes are based on pronouncing "tau" like "tao". No. Tau rhymes with saw.Tao rhymes with dow. They aren't homonyms like "pi" and "pie".

There is no substitute for the old pi puns. One thing that makes them especially delightful is that pie is round. A pie is a circle, and pi describes a circle. You can't come up with anything that beautiful with tau.

There are no pastries that sound like tau. There is nothing we have an excuse to eat on tau day.

Now if you will excuse me, I am going to go have some pie.

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