Back in the olden days, Colin entered a proof without words in the Big Mathoff. It was mentioned, in passing, in a New York Times obituary of John Horton Conway.
A book about mental arithmetic? By Rob Eastaway? Count me in! In my fuzzy mental Euler diagram of topics and authors, Maths On The Back Of An Envelope lies in the intersection of several ‘favourite’ circles.
Perhaps paradoxically, this meant I was expecting to be a little disappointed: how can a book, by an author I admire, on a topic I both love and have Strong Opinions about, live up to what I’d like it to be? Luckily, Eastaway’s writing is excellent, even taking into account that you expect it to be excellent.
I have two simple rules for deciding whether a popular maths book is Any Good. Firstly: does it teach me something I didn’t know? And secondly: does it entertain me when treading ground I’m familiar with?
The cover text says How to Fall… is “more than a puzzle book”, which is roughly how I was planning to describe it: twenty-six questions that require an element of mathematical or physical thought, followed by solutions in the obvious bijection.
Puzzle books, for me, are hit and miss – I’ve had a steady diet of pop-maths puzzles for the last three decades, and I’m cynical and jaded enough to expect a book of such things to be of little interest: either I’ve seen most of them before, or I’m just not interested in the topics at hand. Nahin’s book is something like an enthusiastic rookie that shakes me out of my cynicism.
There are many things I admire about Matt Parker (or, to give him his full title, Friend of the Aperiodical, Mathematician Matt Parker) and his work, but probably top of the list is how he switches, apparently effortlessly, between modes. One minute, he’s showing off a fax machine to a group of hard-core geeks with Festival of the Spoken Nerd; the previous, he’s inspiring a “lively” bottom set of year 9s, after putting together a Numberphile video for people somewhere in between.
While Humble Pi – A Comedy Of Maths Errors is pitched firmly at the last of those groups – for a popular maths book to hit the top of the Sunday Times bestseller list, it really needs to be – there’s plenty in it for the others.
The dust is settling on the ninth Big MathsJam, and before I get too sad that it’s nearly a year until the next one, I put down some thoughts about what was so good about this one.