No number has captured the attention and imagination of people throughout the ages as much as the ratio of a circle's circumference to its diameter. Pi–or ? as it is symbolically known–is infinite and, in The Joy of pi, it proves to be infinitely intriguing. With incisive historical insight and a refreshing sense of humor, David Blatner explores the many facets of pi and humankind's fascination with it–from the ancient Egyptians and Archimedes to Leonardo da Vinci and the modern-day Chudnovsky brothers, who have calculated pi to eight billion digits with a homemade supercomputer.

The Joy of Pi is a book of many parts. Breezy narratives recount the history of pi and the quirky stories of those obsessed with it. Sidebars document fascinating pi trivia (including a segment from the 0. J. Simpson trial). Dozens of snippets and factoids reveal pi's remarkable impact over the centuries. Mnemonic devices teach how to memorize pi to many hundreds of digits (or more, if you're so inclined). Pi-inspired cartoons, poems, limericks, and jokes offer delightfully "square" pi humor. And, to satisfy even the most exacting of number jocks, the first one million digits of pi appear throughout the book.

A tribute to all things pi, The Joy of pi is sure to foster a newfound affection and respect for the big number with the funny little symbol.

CUSTOMER REVIEWS (Average Customer Rating: 4.0 based on 37 reviews)

This is no Joy

I expected a fanciful, light-hearted assessment of the history, development, and understanding of pi. This book is none of those things. There are myriad books on the topic that are better than this. The typeface and its distracting watermarks and background graphics are annoying. Attemps to deal with historical perspective are amateurish. On page 29, Blatner says, "[In]...the Dark Ages...following the breakdown of the Roman Empire and the rise in power of early Christianity...budding scientific interest in Europe...was effectively quelled by religious intolerance..." This statement is historically inaccurate and appears solely to reflect the author's uninformed religious intolerance.
Not only do "zero" modern historians refer to the middle ages as "dark," but the author himself entitles the chapter "A Millenium of Progress!" David, is it "dark" or is it "progressive?" Please fish or cut bait. Further, the chapter continues to describe how progress was made through dialogue among the different relious and ethnic groups of the era. Not only is the history flawed, but the statements are self-contradictory. Poorly done and not at all funny.
November 23, 2008

Fascinating and fun to read

Okay, what do you get when you measure the circumference of a jack o lantern?

Pumpkin pi(e).

This is just one of the many little pleasantries that David Blatner has for readers in this most attractive little gem of an exploration of 3.14159.... There's also some pi poetry, some of which is not half bad. There are pi mnemonic devices, words strung out in prose or rhyme with the length of the individual letters to remind one of the string of pi digits. For example, "How I wish I could calculate pi." Or, "Sir, I bear a rhyme excelling/In mystic force and magic spelling...." In the same chapter, "Memorizing Pi" Blatner recalls some of the great mnemonic exploits of pi-dom, culminating in the incredible feat of one "Hiroyki Goto, who in February 1995 spent just over nine hours reciting 42,00 digits of pi from memory." (p. 111)

One of the questions I always had about pi was, Are the digits random? The number is irrational and transcendent so apparently the numbers never repeat. To me that always sounded like something close to a definition of a random sequence. Here I learned that in the first million digits, there are 99,959 zeros, 99,758, ones, 100,026 twos, 100,229 threes, 100,230 fours, 100,359 fives, 99,548 sixes, 99,800 sevens, 99,985 eights, and 100,106 nines. I would consider that distribution indistinguishable from random. Incidentally the first one million digits are printed in the book, albeit in such small type that you'll need a magnifying glass to make out the numbers.

But could the seeming randomness of the digits change as more and more places are calculated? Apparently not since "now, at over 51 billion digits on record, it appears that there's no statistically relevant difference..." between any of the numbers. (p. 73)

Blatner has a chapter on "The Circle Squarers." These guys are still hard at work trying to square the circle, something I have been told that not even God can do. Some of the tries are very amusing. People who work at trying to square the circle may be compared with those who work on building a perpetual motion machine.

Also interesting is how the present value of pi was arrived at over the centuries and the various ways people tried to get it as exact as possible. In the chapter on "The History of Pi," Blatner recalls the "earliest known record of the ratio" which "was written by an Egyptian scribe named Ahmes around 1650 BCE." He reckoned that pi equaled 256/81 or 3.16049. Blatner reports that the Romans used three and an eighth as close enough even though they knew three and a seventh was more accurate, simply because three and an eighth was easier to work with. (p. 20)

The book is filled with art work sometimes superimposed over the relentless march of the digits of pi in something like one-point type. There are many sidebars with interesting tidbits about pi and quotes from famous mathematicians. The book is fun to read and would make a nice little gift for the budding mathematician in your family or CIRCLE of friends.

May 05, 2008

A good beginning, but only a beginning

When you begin to read a book that's about six inches by six inches square and 120 pages, you can't expect a masterwork. That being said, Blatner does a decent-enough job giving a cursory look at the number pi, its history, and the current state of research and application. The weakest (by far) section is the first, historical section. Blatner has done most of his writing on scientific and computer-related issues, and as such I guess it is to be expected that his view of history is weak. His incredulity that people who lived thousands of years ago did not hold the same sort of precision on pi as he does tends towards a condescension that does not fit the situation. Beyond this, however, it's a good first step, and it would be a good only step for someone who doesn't want to do a ton of heavy lifting to get a quick, informative read.
March 17, 2008

This book is cool!

This book was fascinating, and I learned alot on pi day.
On march 14 (Pi day) I had memorized 50 digits, and wowed my classmates.
I reccomend this book to any budding Pi researcher/memorizer
March 14, 2007

What nonsensical packaging

The Joy of Pi is a little book. It is little in that it is printed in a small format. It is also little in that it stretches to fill 144 of these little pages. It is also little in that it contains lots of fluff rather than quality information. About the only thing that this book is big in is in its profuse use of graphical elements and downright nasty anecdotes for people who were mistaken about the value of Pi.

For such a topic, I would have expected much more content than was delivered here. This book runs to 144 pages but once you strip off all the extraneous stuff, it is probably a 15 or 20 page essay on the history of Pi. This history is actually quite interesting and reasonable well written. We, the readers, are told about the ongoing development of this number from the earliest attempts to calculate it, through all kinds of erroneous attempts, to several successful equations and algorithms. Since the history of mathematics as a whole goes from the Egyptians, to the Greeks, to the Arab, Indian, Chinese and then back to the Europeans, it is nice to see them all mentioned in this little book.

Once we reach the 20th century though, the book runs out of steam. Now we are provided multiple chapters that speak of the quest to find more and more digits of Pi with the record being at some 52 billion at the time of the book's writing. But, since there is very little of interest in recording each improvement from 4500 terms to 52 bilion terms, the author tries to lighten up the story by adding all kinds of anecdotes about the solvers. So, we are provided a whole chapter on a pair of Russian brothers who built their own supercomputer in their Manhattan apartment to do these calculations. Why is this story worthy of a full chapter while everyone who came before then has to be satisfied with only a sentence or paragraph? No idea except for my conjecture that the book was going to be too short without this kind of expansion.

Another chapter is devoted to the antics of several people who attempted to "solve" pi via other means and failed. This book does not spare them and ridicules their efforts to an excessive degree. It is as if the fact that some people made mistakes, and some would not admit to them, was a personal affront to the writer. Why spend many pages quoting from the writings of these people and making fun of them?

The largest space filler in this book though, is the printing of the first one million digits of Pi. Yes, you read that right! The first one million digits are printed. Since they are printed in a size that requires a magnifying glass to read, I am strengthened in my conjecture that space filling was the real reason for this.

Since there is so little real text provided, most of the space of the book is filled with these kinds of shenanigans. The most egregious factor for me was the constant playing with different typefaces and sizes of fonts. It has been known since the early 1980's that just because your computer CAN display many fonts, that it is NOT A GOOD IDEA to do so as readability suffers. However, in this tome, the author engages in that practice and to make it even worse, adds all kinds of useless graphics and drawings and bubbles and circles and angles and other things to cluter up the page. This is typically printed in a really ugly shade of green that even further depresses the spirit by making it harder yet to read the text.

So, all in all, I would urge everyone to pass on this monstrosity of a little book. If you really want to learn more about Pi, there are other books that are much more readable and informative than this one. Save your money.
January 22, 2007

SIMILAR PRODUCTS

e: The Story of a Number
by Eli Maor

Zero: The Biography of a Dangerous Idea
by Charles Seife

An Imaginary Tale: The Story of "i" [the square root of minus one]
by Paul J. Nahin

The Golden Ratio: The Story of PHI, the World's Most Astonishing Number
by Mario Livio

A History of Pi
by Petr Beckmann