jrosenhouse | January 28, 2012The Big Sudoku Book has received another review, and in an unexpected venue: The Wall Street Journal! The review is by Keith Devlin, a mathematician at Stanford University and the author of a small library of books of his own. Devlin writes:
The authors show vividly that mathematics is really about the power of abstraction, the push to explain as much as possible in the most compact form possible. Numbers and arithmetic are a part of that enterprise, but there is a lot more besides. “Taking Sudoku Seriously” is an excellent vehicle whereby devotees of the puzzle can come to understand the…
jrosenhouse | January 27, 2012Over at Talking Philosophy, Mike LaBossiere offers a defense of teachers's unions. He is a bit too tame for my taste, and he is far too respectful towards anti-union arguments that have far more to do with general hostility to public education than they do with measured criticism, but in the end he arrives at the right place:
In general, it would be rather odd if unions did not cause some problems. If they did not, they would be truly unique. However, it seems more sensible to address these problems rather than simply condemning unions. Given the fervor with which these unions are being…
jrosenhouse | January 25, 2012Well, the BSB (that's the Big Sudoku Book) has now received its first review. It comes from Ed Pegg Jr., who runs an excellent website about mathematical games and puzzles and is very well-known among those interested in recreational mathematics. Did he like the book?
Along with Sudoku Masterpieces and Mutant Sudoku, this is one of the best Sudoku books ever written. And I do mean written/crafted -- too many Sudoku books are computer generated. This book shows a lot of careful craftsmanship.
He did! Go check out the rest of the review. Then go buy multiple copies before they are all…
jrosenhouse | January 24, 2012Since my little break has turned out to be longer than I anticipated, I fear that my blog muscles have atrophied a bit. So let's start flexing them again by revisiting a familiar topic: Adam and Eve.
Over at HuffPo, Peter Enns makes another contribution to the genre that tries to explain why evangelical Christians should not be troubled by the fact that science completely refutes the traditional understanding of Adam and Eve. He gets off to a good start:
If evolution is right about how humans came to be, then the biblical story of Adam and Eve isn't. If you believe, as evangelicals do…
jrosenhouse | January 10, 2012In honor of the publication of the BSB (that's the Big Sudoku Book, for those not up on the local slang), my coauthor, Laura, and I hosted a session at last week's Joint Mathematics Meetings about the mathematics of Sudoku. I gave the opening talk in the session, an overview of some interesting mathematical questions that arise naturally from thinking about Sudoku. Of course, I had a slide discussing what, until recently, was considered the biggest open problem in this area: What is the minimum number of clues a sound puzzle can have?
Of course, everyone knew the answer was 17. After all…
jrosenhouse | January 2, 2012I have a general policy of not blogging when I'm on the road, but I couldn't resist poking my head up to call your attention to this article, by Paul Wallace, over at HuffPo. Follow the link to see why...
jrosenhouse | December 31, 2011Tomorrow I will observe New Year's Day by hopping into the Jasonmobile and driving to my New Jersey office. Which is to say, I will be visiting my parents. Then on Tuesday I shall hop on a train and sally forth to Boston, which is hosting the annual math extravaganza knows as the Joint Mathematics Meetings. Lots of math, lots of socializing, what's not to like? I won't be arriving back in Harrisonburg until Sunday the eigth. Alas, on Monday it's right back into the classroom for the spring semester.
Which is to say, I won't be posting anything for a little while. Now, now, let's have…
jrosenhouse | December 30, 2011Michael Ruse has written another post about morality. Sadly, he hasn't really clarified much of anything. Throughout this discussion his position has been that there are moral facts that we come to know through non-scientific means. I have been trying to understand how he justifies either part of that, but I'm afraid I still have no idea.
He writes:
First, the complaint that since I think morality is a product of evolution through natural selection, I must therefore be using science to justify my ethical claims. I too am committing the naturalistic fallacy. Not so. Distinguish between…
jrosenhouse | December 28, 2011Time to show you the dramatic conclusion to the story I began yesterday.
Our problem was to define the complex exponential function in a way that was consistent with everything we knew about real exponential functions. We noticed that one of the standard rules for exponents implies
\[
e^{x+iy}=e^xe^{iy}.
\]
Since we already know how to deal with the first term in that product on the right-hand side, our problem has been reduced to deciding what to do with “pure imaginary” exponents.
The key to doing that is to remember that we have a Taylor series expansion for the exponential function…
jrosenhouse | December 27, 2011Euler's identity is the equation:
\[
e^{i \pi} +1=0.
\]
If you have any taste for mathematics at all, it is hard not to smile at this. In one equation we have each of five “special” numbers (e, i, pi, 1 and 0), along with one instance of each of three basic arithmetic operations (addition, multiplication and exponentiation.) Not too shabby!
But why is the equation true? Well, the first thing to notice is that we have an imaginary number in the exponent. That means that appreciating this equation requires an understanding of how we deal with such things. Towards that end, we have the…
jrosenhouse | December 26, 2011My earlier post on this subject was entitled “What is Scientism?” because, while I have seen the term thrown around in a number of venues, I have never been entirely sure what it means. Having had a chance now to digest some of the arguments raised in the comments, as well as the thoughts expressed at other blogs, I think it's time to go another round.
The first point I made in my earlier post was that, in the context of science/religion disputes, to be accused of scientism was to be accused of being insufficiently respectful towards religion. A perfect example of what I had in mind is this…
jrosenhouse | December 23, 2011
The BSB (that's the big Sudoku book, for those not up on the local slang) is now available! It's both a math book and a puzzle book. As math book it contains a survey of some of the mathematical aspects of Sudoku puzzles. For those familiar with the BMHB, the present book is considerably less technical. A few sections are tough going, but most of it should be accessible even on a casual reading. Indeed, one of the points of the book is to use Sudoku puzzles to introduce ideas from higher mathematics.
As a puzzle book it contains close to ninety original puzzles for your solving…
jrosenhouse | December 22, 2011This is Emily:
She sure does look comfortable, doesn't she? And why shouldn't she be? In a tour de force of inductive reasoning she figured that today would be like the previous 364 consecutive days, at least to the extent that I wouldn't even consider stuffing her into a box and bringing her out to my car.
But she was wrong.
“Why is God angry?” she asked.
I explained that while this sudden intrusion into her happiness may seem incomprehensible form her limited, feline perspective, she should remember that I can see the big picture. I understand, in a way that she cannot, that…
jrosenhouse | December 20, 2011You should read Ross Douthat's obnoxious eulogy for Christopher Hitchens just so you can enjoy this magnificent takedown from Charles Pierce, over at Esquire. Pierce writes:
For the sheer magnitude of its horsepucky, this column may well stand forever. Generations yet unborn will come and read it, just to stare out of the magnificent vista of presumption, self-regard, and tinpot piety the way people bring their children to look at the Grand Canyon. It takes an unusual amount of juice-box hubris to put your thoughts in a dead man's head. It takes towering presumption to put into a dead man's…
jrosenhouse | December 19, 2011Michael Ruse has now written a second post on the subject of scientism. He gets down to business in the second paragraph:
My three examples of nonscientific truths were mathematics, morality, and answers to those kinds of philosophical meta-questions, like - “What is the truth status of claims that only scientific claims are knowledge claims?” I will leave the first and third categories for discussion at another time, although frankly I will say that if someone really thinks the Euler identity (my example) is a generalization from experience then they are in the right state of mind to…
jrosenhouse | December 18, 2011In a HuffPo essay entitled “Why I Love Religion,” Rabbi Alan Lurie writes:
I love the holy texts, the rituals, the art, the histories, the practices, the mystical teachings and the sacred spaces. I love religion, while very aware of its obvious dangers and limitations, because for the last 15 years religion has provided insight, intellectual growth, friendships and inspiration that continue to transform my life for the better.
We're really not on the same page here. I agree with him about the art, and I'm not sure what he means by “the histories,” but I find nothing to admire in the…
jrosenhouse | December 17, 2011If you spend much time involved in science/religion discussions, you will inevitably hear the term “scientism” thrown around. Usually it is hurled as an epithet. In practical terms, to be accused of scientism is usually to be accused of being insufficiently respectful of religion.
But I've never entirely understood what scientism actually is. The usual definition is that scientism is the blinkered belief that science is the only reliable “way of knowing,” but this is vague until we have sharp definitions of “science” and “way of knowing.” Philosophers have devoted no small amount of…
jrosenhouse | December 16, 2011By now I'm sure everyone has heard that Christopher Hitchens has died. I don't have much to add to what everyone else has said, so I'll keep this short. I regard God is Not Great as a masterpiece, and if that had been the only thing he ever wrote, then, as we like to say at Passover, dayenu. Whatever the topic, to read Hitchens, or to hear him speak, was to gain an appreciation for what the English language could me made to do.
Hitchens wasn't always right (his disastrous support for the Iraq war and his cartoonish hatred of the Clintons come immediately to mind), but he was so eloquent…
jrosenhouse | December 8, 2011It occurs to me that I haven't done a chess post in a while. It's possible that I'm the only one unhappy about that, but there's actually a big chess story in the news. You see, for the first time in nearly twenty years, an American chess player has defeated a sitting World Champion. The American player is Hikaru Nakamura. The champ, from India, is Viswanathan Anand. This all went down on Tuesday at the London Chess Classic. More than that, as a chess fan let me just say this: Boy howdy! What a game!
It is sometimes said that top chess players are either perfectionists or pragmatists…
jrosenhouse | December 6, 2011Blogger R. Joseph Hoffmann recently posted a stunningly idiotic essay lamenting the present state of atheist discourse. It's standard fare for him, this time expressed in especially pretentious and contentless prose. For example, I defy you to discern anything sensible in these two paragraphs:
Atheism has become a very little idea because it is now promoted by little people with a small focus. These people tend to think that there are two kinds of questions: the questions we have already answered and the questions we will answer tomorrow. When they were even smaller than they are now,…