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100 Essential Things You Didn't Know You Didn't Know

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If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is.

John von Neumann




Mathematics can tell you things about the world that can't be learned in any other way. This hugely informative and wonderfully entertaining little book answers one hundred essential questions about existence. It unravels the knotty, clarifies the conundrums and sheds light into dark corners. From winning the lottery, placing bets at the races and escaping from bears to sports, Shakepeare, Google, game theory, drunks, divorce settlements and dodgy accounting; from chaos to infinity and everything in between, 100 Essential Things You Didn't Know You Didn't Know has all the answers!

304 pages, Kindle Edition

First published January 1, 2008

47 people are currently reading
922 people want to read

About the author

John D. Barrow

89 books166 followers
John D. Barrow was a professor of mathematical sciences and director of the Millennium Mathematics Project at Cambridge University and a Fellow of the Royal Society.

He was awarded the 2006 Templeton Prize for "Progress Toward Research or Discoveries about Spiritual Realities" for his "writings about the relationship between life and the universe, and the nature of human understanding [which] have created new perspectives on questions of ultimate concern to science and religion".

He was a member of a United Reformed Church, which he described as teaching "a traditional deistic picture of the universe".

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5 stars
78 (15%)
4 stars
160 (31%)
3 stars
183 (36%)
2 stars
65 (12%)
1 star
16 (3%)
Displaying 1 - 30 of 67 reviews
Profile Image for David.
384 reviews13 followers
October 10, 2014
This collection of short, essay style chapters (100 chapters in 277 pages)is great for random reading (as I have done while eating breakfast). For those with an interest in sports, there are a great many interesting sports related math items, though the sports include those which are opaque to American readers, such as Cricket. The math is not complicated, but the thinking involved does cause the reader to delve into real world issues, well beyond sports alone.

This is precisely the kind of book that could turn a math-a-phobe into a more math curious student. Each chapter presents the reader with humor, questions and some clear idea of problems that can only be solved by mathematical methods.

Profile Image for Thomas Ray.
1,506 reviews521 followers
December 18, 2018
Tells us too little. In the 5-body gravitational problem, doesn't describe the motion or initial conditions of the small body, nor explain clearly what happens or why. Says the bodies would move apart with infinite speed by Newton's laws, and leaves it there. If you were going to say anything on this, it should've at least been a description.

Whole book so. Too little.
35 reviews
Read
June 16, 2009
I found this book in Barnes and Nobles and subsequently got it as a birthday present. Not wanting to disappoint my parents, I decided to read it. Despite it being boring at first, I actually found it to be quite enjoyable midway through. The book essentially explains how all your common occurances in life link back to mathematics. My personal favorite is an explanation of why people often gripe about find themselves in the longer line at a store or a post office. The simple explaination is because people often have a higher probablity of gettting in the longer line. Another possibility is because maybe the lines are going the same speed but in your eyes the other line seems to be going faster.
I really enjoyed this book because it gave a lot of reasons for all of life's common occurances. Even though some of the jargon was a bit complicated to understand, I still found the book quite enjoyable.
I would reccommend this to anyone who simply wants answers or to anyone who enjoys math.
302 reviews
April 6, 2010
If you like math, you'll like this book, but you can probably get along just fine without knowing any of the 100 things about the mathematics in the world; most people do. In fact, most people would probably not be at all interested in the majority of things in this book.

If you don't like math, maybe you will like it after reading this book. But you probably won't. I've found that the things I find most exhilarating about math bore a lot of people.


Profile Image for Jerry Smith.
883 reviews17 followers
January 30, 2013
As a dedicated math hater and one who finds mathematical expressions of anything confusing and frustrating, I thought this might be a good book for me. It is quite fun and there are several items of interest among the 100 chapters.

The book is written in small snippets - each chapter tackles a differnet topic and they are all 2 to 5 pages long at the most. Some are much more mathematical than others. Indeed, some seem to be only very remotely related to math which makes the subject for that chapter a bit of a reach.

Conversely, there are some chapters that almost immediatey dive into what are, for me, complex formalae which lost me right away. The beauty of a book like this is that you can simply skip to the next section when something doesn't interest you, since they all stand alone.

Barrow writes well and the book is entertaining and worth a read especially if you are looking for something not too taxing. He also managed to explain in about 4 paragraphs, the "Monty Hall Problem" which another author took almost a quarter of a book to acheive!

Definitely some interest here and of the 100 topics, I would say that around 10 were actually truly something that a) I didn't know and b) were things that I cared about!
Profile Image for Mike Crawford.
225 reviews
October 15, 2009
The book is comprised of 100 short chapters of 2-3 pages in length. I spent a week reading this book (it feels more like reading a blog where the author's goal is brevity), and a day later....I can probably name 5 memorable topics, and 2 were interesting enough for me to wikipedia the idea presented in the short chapter. And probably half the topics will be very familiar to those people who would possibly check this book out from the library. The book seems to be a series of "abstract" summaries of 100 math-y sort of topics. And you must go elsewhere for any real amount of detail.
914 reviews5 followers
November 12, 2016
Fun, enjoyable, and completely mistitled. These are little anecdotes and trivia with some mathematical twist, but one of the chapters is devoted to an anecdote about Igor Tamm solving a mathematical problem to establish his bona fides as a mathematician during the Russian Revolution -- great trivia, but hardly essential. (The story is quoted http://math.stackexchange.com/questio... )

Each chapter is just a few pages long and a quick read.
20 reviews1 follower
August 2, 2009
This book tries really hard to make mathematics interesting but even after compressing so many different short stories into brief chapters that cover a couple of pages each, I still couldn't find the topics covered to be at all interesting. There were a few nuggets in there that made it semi-worthwhile though, such as the mention of a couple of obscure and funny incidents and/or websites. "Pylon of the Month" is one of those sites.

Skim. Don't read. Definitely don't purchase.
Profile Image for Ben.
49 reviews
July 17, 2010
As an engineer and fairly geeky person, I did know I did know a lot stuff in this book already. And I think even non-geeks would know some of these things. Or at least know they don't know it...

Some of the explanations would have been easier to understand with a diagram, equation, or chart. And I think the author could have gone deeper on some topics.
Profile Image for William Lubold.
50 reviews
January 4, 2011
By all rights, I should have loved this book. I did not. It takes a special kind of writer to take an interesting topic and make a boring book out of it. And by "special," I mean, "bad." There you go.
Profile Image for Cassie.
15 reviews10 followers
July 12, 2010
this promised to be an interesting read, but the entries were short and sometimes seemed rushed. it might have benefited from having fewer chapters and going into more detail.
2,416 reviews6 followers
June 12, 2016
Abandoned after about the first 15 things. Each section is too short and superficial.
108 reviews3 followers
December 25, 2024
Kinda boring in the end - not sure how essential most of these things are, and also a lot of the scenarios in the book just make assumptions at the start that don't really make much sense just so we can get to the math.

Ironically, there's a few spots in the book where the author is critical of the overuse of math, but I feel they fall into that trap a few times throughout this book.

But if you're going to create a mathematical formula for what counts as a mandate based on the premise that you need to ensure most people voted for a candidate beyond statistical noise, and then pick the US as the example system to apply this to, you should probably at least attempt to explain why you're using the electoral vote rather than the popular vote based on the initial premise, since they're not equivalent and there's no guarantee the electoral vote winner had the majority of voters case ballots for them.

Maybe I just misunderstood this example, but it's one of several where I don't really think the author's assumptions made any sense, they just wanted to get to the math as soon as possible.
Profile Image for Katharina Klose.
188 reviews
March 6, 2022
Obwohl das Buch ja auch für Mathe-Hasser ausgeschrieben ist (ich hasse Mathe zwar nicht unbedingt, aber mögen tue ich es auch nicht), war es mir teilweise einfach zu hoch. Ich konnte da aber relativ leicht darüber hinwegsehen und habe die Ausführungen als gegeben hingenommen.

Der Schreibstil ist angenehm zu lesen und ist mit viel Humor witzig und es macht Spaß, das Buch zu lesen.

Generell würde ich das Buch aber eher den Menschen empfehlen, die Spaß an Mathe haben und sich dafür interessieren.
Profile Image for Niklaus.
497 reviews21 followers
October 15, 2023
Libro interessante ... se siete predisposti. Nel senso che su 100 argomenti/curiosità trattate, ciascuna in media occupa due facciate, credo sia improbabile non trovare argomenti di interesse.
Vero che spesso e volentieri usa la matematica (semplice) per dimostrare il perché dei quesiti ma questo è semmai un pregio e, nel caso siate allergici, potrete saltare il paragrafo e arrivare alla conclusione predigerita per voi.
Profile Image for Juan Antonio.
109 reviews2 followers
December 15, 2024
Lo más interesante es que relaciona las matemáticas con aspectos poco corrientes de la vida cotidiana, como la mejor manera de subir pasajeros en avión, la física de la carrera y el salto etcétera, aunque también con otros aspectos más manidos, como los números primos y la criptografía.
1,420 reviews8 followers
March 20, 2022
This probably should have been called 100 mostly non-essential things you'll find interesting but probably won't remember.
155 reviews2 followers
February 14, 2023
Sometimes difficult to follow, but it contains enough gems to. keep you going con to the next topic. The quotes under the chapter titles are worth the cost of the book.
Profile Image for Steve Sarner.
Author 3 books405 followers
December 13, 2016
This past Thanksgiving long weekend I learned 100 essential things I didn’t know I didn’t know about with math and the arts. Frankly, they are not really essential but they were, for the most part, very interesting.

This was the perfect long weekend book for me. As the title suggests, 100 short (2-3 pages) chapters on an eclectic mix of topics connecting art and science. In between the bustle and interruptions of a busy holiday weekend, I could pick it up and delve into a chapter or two and learn something in a few minutes, much more satisfying than scanning a shallow Facebook or Instagram feed.

Plus there was absolutely nothing related to the 2016 US election. That’s a bonus which may have biased my star rating. ; )

Aspect Ratios, Vickrey Auctions, Roller Coaster Design, Doodles, Dali, the 4th Dimension, Markov, The Art of War and much more (92 more to be exact) in succinct morsels of knowledge. Sure – a lot of the math was over my head but it’s still a fun book that shed light on things I was curious about and introduced me to many more things I didn’t know.

This book is definitely not for everyone and as one reviewer suggested, it may be better scanned in a book store than bought. However, for the non-fiction science and fact lover, with or without strong math knowledge, it’s a very enjoyable read.
Profile Image for Cheryl Gatling.
1,295 reviews19 followers
Read
August 27, 2013
I was attracted to this book by its clever title. Although I would quibble that most of the things in the book are not essential (you could live a very satisfactory life without ever knowing any of them, and most people do), the subtitle "Math Explains Your World" is very apt. There is a formula for figuring out how many baseball cards to buy in order to get a full set, a formula for figuring out how long an institution is likely to last, a formula for figuring out how high to build a wall so a tiger can't jump out of his enclosure, and for how many guards are needed in an art gallery. Math explains sports performance, credit card numbers, building construction, paper sizes, roller coasters, making change with different coin denominations, how diamonds sparkle. I admit that almost all of the math went over my head. Whenever he started in with a formula, I went into skim mode. But I liked seeing the sheer variety of things that math can do, and I liked that each of the 100 chapters was nice and short, and often included a picture or diagram.
Profile Image for Maurizio Codogno.
Author 67 books144 followers
January 7, 2016
NOTA: questo libro è anche disponibile in italiano (100 cose essenziali che non sapevate di non sapere, tradotto per Mondadori da Elena Mereghetti) ma io ho letto la versione originale.

Questo libro è della serie "curiosità e spigolature": cose che non meritano di avere un libro tutto per loro ma messe insieme raggiungono una massa critica. Rispetto a Math Geek di Raphael Rosen, che ha la stessa struttura composta da cento capitoletti scorrelati tra di loro e di argomento matematico o fisico, il risultato è a mio parere migliore. Le curiosità sono accompagnate da un po' di contesto, e la narrazione, oltre a essere un po' più ampia, è anche molto più personale e quindi meno asettica. Il fatto che i temi trattati non siano tutti strettamente matematici è un vantaggio per chi preferisce variare un po' la lettura: credo che sia fisiologico che non tutto interesserà a tutti, ma secondo me si può sopravvivere lo stesso.
Profile Image for Peter.
32 reviews7 followers
January 12, 2013
This is a neat little nonfiction book, easy to read in short snippets (which of course is why I read it straight through - no, seriously, it's less tiring than one great big book). I'd heard many of the things the title claims I "didn't know" before, and some of them are only very tangentially related to math, but it's well-written and fun to read anyway. I especially liked the Brit-centric writing; nonfiction books intended primarily for US audiences often have a certain air of hypersensitivity to political topics, which annoys me and quickly goes out of date, whereas this book thinks nothing of remarking (as a conclusion to the section on efficient ways of making change) that the American set of coins is almost the most efficient possible one but if they/we replaced the 10-cent dime with an eighteen-cent piece it would be even better. :D I thought that was cute.
Profile Image for Simon Watkins.
1 review
January 24, 2014
I think this book is most likely to appeal to those who already have a good grounding in mathematics and physics, but have never thought to apply them to the mundane or quirky. For example, there are brief articles on queue selection, how to run a marathon, roller coaster design, the life-saving value of calculus, how to win the lottery (not that helpful, actually), how to get a smooth ride on a bike with square wheels (still less helpful, but surprising). Each section is but two to three pages long, making it a good snacking book rather than a sit down reading feast.
Displaying 1 - 30 of 67 reviews

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