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## This Is How the Number 3.14 Got the Name 'Pi' (time.com) 133

An anonymous reader shares a Time article: Ancient research on real numbers likely "didn't get improved upon until the age of Newton," says John Conway, mathematics professor emeritus at Princeton University who once won the school's Pi Day pie-eating contest. Sir Isaac Newton recorded 16 digits of pi in 1665, later admitting that he was "ashamed" of how long he had worked on the computations, as it meant that he had "no other business at the time," per the MAA. It was not until the 18th century -- about two millennia after the significance of the number 3.14 was first calculated by Archimedes -- that the name "pi" was first used to denote the number. In other words, the Greek letter used to represent the idea was not actually picked by the Ancient Greeks who discovered it. British mathematician William Jones came up with the Greek letter and symbol for the figure in 1706, and it was popularized by Swiss mathematician Leonhard Euler, Catherine the Great's mathematician, a few decades later. "Euler was a much better mathematician than the people who used [pi] before, and he wrote very good textbooks," says Conway. "He used it because the Greek letter Pi corresponds with the letter 'P'... and pi is about the perimeter of the circle."
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## This Is How the Number 3.14 Got the Name 'Pi'

• #### First Post (Score:3, Funny)

on Tuesday March 14, 2017 @11:23AM (#54036815)

Where's my pie for first post?

• #### Re:First Post (Score:5, Insightful)

on Tuesday March 14, 2017 @12:26PM (#54037311) Homepage Journal

It's interesting, because despite Euler's official story about perimeter, the English spelling of 'pie' was very much in use at the time, and as everybody knows, if you hold '3.14' up to a mirror, it spells 'PIE'.

Not that math geeks would ever abide in-jokes.

• #### Re: (Score:2)

Wow - I had never seen the 3.14 in a mirror thing before! Thanks.

• #### It's not 3.14. It's 3.141592653589793238462643... (Score:2)

Even Newton knew that, as per TFA.
• #### Re: (Score:1)

I thought Newton only calculated up to 3.14159265358979 (15 digits)
• #### Re: (Score:2)

Nope, your number isn't even substantially more accurate - what's the difference between three significant digits and 25 in the face of infinity? Nearly nothing, except for the fact that it's a rare calculation that gets any real-world benefit from more than three significant digits. (well, outside of banking I suppose...)

• #### Re: (Score:2)

>> what's the difference between three significant digits and 25

Said no computer science major, ever. (Look up the effect of iteration on small differences, then study up on damping, etc.)
• #### Re: (Score:1)

>> what's the difference between three significant digits and 25 Said no computer science major, ever. (Look up the effect of iteration on small differences, then study up on damping, etc.)

Except, you know... that's not what he said. What he said is

what's the difference between three significant digits and 25 in the face of infinity

which taken in the context of mathematics is an accurate observation. The difference in accuracy between three significant digits and twenty-five significant digits as the requirement for perfect accuracy approaches infinity, is zero. (Look up "Calculus 101", then study up on limits at infinity, etc.)

• #### Re: (Score:3)

nonsense, need a few more digits in machining, optics, space exploration, etc.

• #### Re: (Score:2)

what's the difference between three significant digits and 25

Ummm...one is for blacksmiths and one is for astronauts?

• #### Re: (Score:1)

That would be the difference between a clock that keeps reasonable time, and one that loses over 40 seconds a day.
• #### Re: (Score:1)

Fair enough, but just for fun I would like to to live in a country where people know that pi = 4 * integral(sqrt(1-x^2),x,0,1)) --https://www.wolframalpha.com/input/?i=4+integral(+sqrt(1-x%5E2),x,0,1) -- http://i.imgur.com/VyUvzQK.png [imgur.com]
• #### Re: (Score:2)

So Newton wasn't smart enough to figure out that the true circle constant is Tau, not Pi?
• #### thanks (Score:2)

that was easy.
• #### Divide a circle with radians... (Score:2)

... and you have a sliced pie.

If the number had been discovered recently it would probably have been called pizz(a).

• #### Re: Divide a circle with radians... (Score:1)

Mmmmm ... Pizza Pi !!!
• #### Re: (Score:2)

And Pizza Pie is cut with a circular blade. Coincidence? I think not!

• #### Re: (Score:2)

What kind of barbarian cuts their pizza with a circular blade? It's a meat cleaver from above the shoulder or nothing. How else are you expected to get the proper ratio of pizza to shattered pizza stone right?

• #### Re: (Score:2)

It was named pi, not pie. And the greek letter pi is pronounced like pea and not like pie.

• #### Re: (Score:2)

Sense of humour failure or perhaps you just can't spot a joke?

" And the greek letter pi is pronounced like pea"

No, it isn't, not in English either american , british or australian.

• #### Re: (Score:2)

In Greek, you are correct: https://www.youtube.com/watch?... [youtube.com] (Learn to Read and Write Greek - Greek Alphabet Made Easy - Greek Characters Pee and Seegma)
• #### Re: (Score:3)

To calculate the surface area (a) of a pizza with radius z:

Pi * z * z = a

This formula was discovered by Sir Cumference, one of the lesser-known knights of the Round Table.

• #### With today's low information and alternative facts (Score:1)

by Anonymous Coward
Now would be the perfect time to re-introduce this failed pi legislation [wikipedia.org]
• #### It's Pee not Pie (Score:1)

Why use a foreign letter and use a false pronunciation? Î or Ï are pronounced as the english P or p. Also Î or Ï are not pronounce as you think. You may see it as ÎÎ±Ï... in the greek alphabet, but Î±Ï... is either pronounced as af or av, so ÏÎ±Ï... is pronounce the same as tough(as in stronk).
• #### Re: It's Pee not Pie (Score:1)

Ooohhh... Great, it seems thst the encouding is broken. Last time I checked it was 2017
• #### Re: (Score:2)

Ooohhh... Great, it seems thst the encouding is broken. Last time I checked it was 2017

The /. commit log is from 2003, though. :/

The owner before the owner before the owner was going to sync up with that other site that tried to fork /. and fixed up the code but didn't manage to attract the user base. I'm not being coy, I've legitimately forgotten its odd name - somebody please add it here.

Instead we have half-page ads that make it impossible to interact with the content - one wonders if the editors are al

• #### Re: (Score:2)

Soylentnews.org Interesting what they've done with their fork of the code.

• #### No one has said this yet... (Score:5, Informative)

<mike.shawaluk@gm ... com minus author> on Tuesday March 14, 2017 @12:22PM (#54037273) Homepage
... but yes, it's "that" John Conway. [wikipedia.org]
• #### Re:No one has said this yet... (Score:4, Interesting)

on Tuesday March 14, 2017 @03:52PM (#54038917) Homepage

I was going to mention that, but honestly, he's not thrilled [youtube.com] with that being what he's best known for. "I used to say, and I'm still inclined to say occasionally, that I hate it. I hate the Game of Life."

• #### Re: (Score:2)

I'm sorry he doesn't like being identified with the Game of Life, but it has a special place in my personal software development history. It was one of the first computer programs I wrote in 1971 after graduating from high school, after reading the original articles about it in Scientific American.
• #### Re: (Score:2)

Those were the days. I'm guessing it was a Martin Gardner Recreational Mathematics article as well.
• #### Unicode? (Score:3)

on Tuesday March 14, 2017 @12:27PM (#54037319)

Lesse... Pi is a unicode character that most computers can display.

It should appear here >>

Nope... Come on...

• #### Re: (Score:2)

Well met! Proof positive we think we are a lot smarter than we practice.

• #### pi != 3.14... (Score:1)

by Anonymous Coward

Or, at the very least, 3.14 is a terrible approximation of pi, which is far closer to 3.141592653589793238462643383279502884197169399375105820974944592307816406286 208998628034825342117067982148086513282306647093844609550582231725359408128481 117450284102701938521105559644622948954930381964428810975665933446128475648233 786783165271201909145648566923460348610454326648213393607260249141273724587006 606315588174881520920962829254091715364367892590360011330530548820466521384146 95194151160943305727036575959195

• #### Re: (Score:1)

Could this possibly be correct? I found a double zero in the middle of it.
• #### Re: (Score:1)

Oops, I missed a triple zero near the end.
• #### Re: (Score:2)

Irrational post warning.

I look forward to further instalments, as this is so far woefully incomplete.

• #### Also amusing: Why we solve for "X" (Score:2)

The Arabic scholars solved for "unknown thing, " which was translated by Spaniards into Greek as "X." Or maybe Descartes popularized it. http://gizmodo.com/why-we-use-... [gizmodo.com]

• #### "Came up" with pi? (Score:2)

Jones came up with the Greek letter and symbol for the figure in 1706...

Umm, the Greek letter is the "symbol." The summary (or actually the Times article that the summary, as usual, plagiarizes, though this time they at least made an awkward attempt at attribution) makes it sound like the Greeks had this letter "pi" but no "symbol" to actually use to write it, which is as absurd as claiming, for example, that Gosset (aka Student) came up with the English letter and symbol "tee"/t to represent the result of his test of statistical significance.

• #### Catherine the Great's Mathematician? (Score:4, Insightful)

on Tuesday March 14, 2017 @01:33PM (#54037965)

Do we really need to invoke Catherine the Great's name to help explain who Leonhard "one-of-the-greatest-mathematician's-of-all-time" Euler was? For me it would be more like "Catherine the Great, a sponsor of the legendary Euler, also happened to do some notable things while leading Russia".

• #### Re: (Score:1)

Mod parent up!

• #### The Pi Symbol is Nonsense (Score:2)

The pi symbol could easily be replaced with something that depicts the representation between radius and circumference, freeing up a tiny bit of learned memory for everyone who uses math. There is no reason to use a purely symbolic constant to represent a naturally occurring relationship. Save the ancient Greek symbols for meaningless artifacts which only occur in math space.

I understand that many people who would write that this is not necessary, would also write that they would not want to have to relearn
• #### Re: (Score:2)

The pi symbol could easily be replaced with something that depicts the representation between radius and circumference, freeing up a tiny bit of learned memory for everyone who uses math. There is no reason to use a purely symbolic constant to represent a naturally occurring relationship. Save the ancient Greek symbols for meaningless artifacts which only occur in math space. I understand that many people who would write that this is not necessary, would also write that they would not want to have to relearn the new symbol, thereby proving a point that it took too much effort to lean the old one.

Lots of things potentially replaced by icons, I suppose. But doesn't your argument apply equally well to the western 26-letter alphabet itself?

Why go through so much effort of learning those silly "letter" thingies, when we could be using emoticons or classic Chinese picture inspired words or hieroglyphics and "save ourselves so much trouble"?

• #### Re: (Score:2)

Why go through so much effort of learning those silly "letter" thingies, when we could be using emoticons or classic Chinese picture inspired words or hieroglyphics and "save ourselves so much trouble"?

I suspect that given the way emoticons are taking over chat and the fact that the Chinese are taking over the economy, we may be heading in that direction...

• #### Re: (Score:2)

There is no reason to use a purely symbolic constant to represent a naturally occurring relationship.

How can you ever represent it except in a symbolic way? That's what symbols do. That's what "representation" is.

A circle with a line across it? That's still a symbol, and you still need to learn what it means.

would also write that they would not want to have to relearn the new symbol, thereby proving a point that it took too much effort to lean the old one.

No, it means it took almost no effort to learn the old one, and it's not like anyone ever really forgets it if they need it, so what's the point in changing it now?

• #### Re: (Score:2)

The pi symbol could easily be replaced with something that depicts the representation between radius and circumference

Can I vote for the new symbol to be Pac-Man?

• #### Re: (Score:2)

PacMan might be a good choice, as it indicates radii and circumferences, and also looks like a pie with a wedge cut out. A pain to draw, though.

As an aside, as a college student, I enjoyed learning new uses for most of the Greek letters, and liked to keep track of which ones didn't have an assigned special meaning yet.

• #### Re: (Score:2)

The pi symbol could easily be replaced with something that depicts the representation between radius and circumference,

Which would not be representational for all the other mathematical uses of pi, a number that shows up a lot in places you might not expect, such as the normal distribution [wikipedia.org].

• #### Re: (Score:2)

The pi symbol could easily be replaced with something that depicts the representation between radius and circumference...

I agree. Tau: the ratio of the circumference to the radius.

• #### Pee and pie (Score:3)

on Tuesday March 14, 2017 @02:27PM (#54038373)

Some years ago I had a university professor who was of Greek extraction, and he pronounced the names of the English and Greek letters the same, "pee". The coursework (communications) involved lots of probability distributions, so both came up frequently. You had to pay attention.

...laura

• #### Conway as in Conway's Life, that is (Score:3)

on Tuesday March 14, 2017 @04:47PM (#54039311) Homepage

John Conway, mathematics professor emeritus at Princeton University who once won the school's Pi Day pie-eating contest.

He also invented Life [wikipedia.org], of course.

• #### Euler was such a hack (Score:2)

Takes something of Archimedes, and makes it his own by giving it a name he gives a faux-Ancient-Greek patina. He stole the other most famous transcendental constant, Oughtred's (or possibly Napier's) 'e', and named it after himself too.

• #### Euler was the man for all symbols! (Score:3)

on Tuesday March 14, 2017 @05:51PM (#54039771)
Euler was the boss, and pretty much invented and standardized the way we write algebra symbols. As Dr. Julius Sumner Miller used to say, he is deserving of your further study!

Also, 3.14 is so undeserving to connect with pi, it might as well just be three. What is still amazing is 355/113, the most accurate fraction for pi with a denominator less than 10,000 or so. (I could be off a little, look it up.)

• #### 3.14 isn't Pi (Score:1)

Pi is the ratio of the circumference of a circle to the diameter. 3.14 is an approximation of Pi to three significant figures. A closer approximation is 3.14159265359
Pi is an "irrational number" which never has a final concrete value. You just get as close as you need to for the accuracy of what you are trying to do. I remember using Pi out to 13 decimal places in undergraduate physics class. ... Picking on the sloppy wording in the article.

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