The Checker Maven

The Other Benjamin

Who among us has not read The Autobiography of Benjamin Franklin, and derived untold benefit from the eminently practical wisdom and philosophy of its author? And who would be surprised to learn that Ben Franklin was himself a checker player, who praised the merits of the game as training for life?

Today's Checker School problem, though, was composed by a different Benjamin: E. A. Benjamin, to be precise, but we think it's as practical and useful, at least in checker terms, as Ben Franklin's advice for living a successful life. The problem situation is shown below.


Black to Play and Win


Taking a closer look, we see that White has a material advantage, having two kings to Black's one, but Black's mobility is clearly superior. Is it enough to turn the situation into a Black win? Try it out, and then click on Read More for the solution, notes, a sample game, and some words of wisdom from the better-known Benjamin.

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06/30/07 - Printer friendly version
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How to Beat Granddad at Checkers

It was our pleasure quite recently to receive in the mail a copy of a wonderful new checker book, John Cardie's How to Beat Granddad at Checkers, and we simply can't say enough good things about it.

Mr. Cardie's book is based partly on the premise that grandparents have a lot to offer to grandchildren, and that many important lessons can be imparted over the checkerboard. So, to a large extent, the book is about much more than checkers: it's about life, and wisdom, and family, and learning, and teaching. It's about precious hours that grandparents and grandchildren can spend together and about the wonderful and irreplaceable memories that these moments create. Mr. Cardie's book speaks to the heart as much as to the mind.

Of course, there's checker content galore, and grandparents will likely learn a great deal themselves. After an introduction which convincingly explains why checkers is a good thing for both grownups and youngsters, Mr. Cardie teaches about the numbered board and checker notation, and then jumps right into basic checker tactics. (Presumably, grandparents can teach the rules and other basics on their own, although there is a later chapter in the book with the official rules of checkers.) Mr. Cardie has invented some very clever new names for old tactics, such as "the sandwich move" for what is traditionally known as "breeches." Some of the names are really catchy, such as "Twins in the Closet" for a particular three king vs. two king endgame. The book as well is liberally sprinkled with pages of general instruction, such as lessons on sportsmanship, and interestingly titled items like "Earnings and Yearnings" and many more, which use checkerboard situations as analogues for life. There are a number of checker puzzles of appropriate difficulty; and a listing of checker websites and resources rounds out the volume.

Some time back, we reviewed Galina Golant's excellent book, Play Checkers With Me. Ms. Golant's book was at the small child, introductory level. Mr. Cardie's book is the next step up, and is suitable for use with children who are a few years older, perhaps from the age of six or seven onwards. But there is no question that adults too will enjoy the book and benefit from it.

We hear that Mr. Cardie may be able to land a national distribution contract for the book through a prominent chain. We're sworn to secrecy about the details, but we certainly hope that comes to pass.

Author John Cardie

Obtaining this book is easy and inexpensive, and something that we recommend you do without delay. Just go to Mr. Cardie's website at for full details on ordering options. It's a book that is not to be missed.

06/30/07 - Printer friendly version
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A Summer of Checkers

In the Northern Hemisphere, it's now officially summer; and what is better in summer than, at a picnic or outdoor gathering, to play a few games of checkers? A cool drink, a slice of watermelon, and a friendly contest or two over the board ... that's life at its best. At least, it usually is....

In today's column, we join Billy (we've already met him in one of our earlier stories), who is off for a month at summer camp. As one of the top players on his school team, Billy has become a sort of informal checker instructor. It's mid-afternoon, and the boys, having just finished a somewhat rowdy game of leap frog in a nearby field, have gathered at a picnic table and are settling down to some checker work.

"Here," said Billy, "let me show you guys one that's kinda like playin' some more leap-frog." He then set up the position below.


White to Play and Win


"Can ya believe it," Billy continued, "White can win this here one!"

The rest of the boys were talking among themselves, expressing more than a little skepticism. "But it don't look so good," objected Willy, one of the younger and less experienced players. "I mean, Black's got a king and stuff!"

Just then Mort arrived with a big plate of watermelon and a tray of sodas. He had been last at leap-frog and so was made to "go fetch" for the other boys. "Well," Mort exclaimed, glancing at the checkerboard as he set down the refreshments, "I ain't so good at leap-frog but I can win that game there!"

The words "yeah, right" were heard repeatedly as the gang attacked the food and drinks. "I can too!" Mort said in a loud and exasperated voice. "I'll show ya!"

Billy sat back a little, put down his soda, and said to the other boys in a firm tone, "Hey guys, give 'em a shot at it." This was accompanied with a bit of a wry grin that Mort didn't catch. "Tell ya what. If he figgers it out, somebody else gets the next tray of sodas. If he don't get it, maybe he needs a bath or somethin'."

Everyone started to laugh except Mort, who realized now that if he didn't find the solution, he was probably going to get summarily tossed into the lake. But there was no turning back. Shaking just a little and hoping the boys wouldn't notice, he sat down at the board.

Don't be all wet yourself. Solve the problem and click on Read More to check your solution.

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06/23/07 - Printer friendly version
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A Real Eye-Popper

We found this problem in a old and rather eclectic checker book. The author, who must have been an eclectic character in his own right, referred to the solution as "a real eye-popper."

You may or may not agree--- after all, what constitutes an eye-popper is in the mind of the beholder--- but we do think you'll enjoy solving this one.


Black to Play and Draw


Forces are even, but Black has a weak man that White can pick off in just a few moves. Can you focus on this one and see your way to a Black draw?

Don't be blinded by the seeming difficulty; clicking on Read More will provide 20-20 hindsight by bringing you the snappy, perhaps even eye-popping, solution.

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06/16/07 - Printer friendly version
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10-Piece Endgame Database Now Available

Here's an astronomy question for our checker fans:

Q. What's denser than the galactic core and has to do with checkers?
A. Ed Gilbert's 10-piece endgame database.

Completed in just under a year (admittedly somewhat faster than the Milky Way galaxy took to reach its present form), and containing the proverbial billions and billions of endgame positions, Ed Gilbert's 10-piece endgame database is dense, rich, and full of checker content. It's the very first product of its type to become available for home use by serious checker enthusiasts, and it is destined to change and enhance top-level checker play as leading players begin to use it for analysis and study.

The concepts involved seem complex on a nearly cosmological scale, so to bring things down to earth, The Checker Maven interviewed database creator Ed Gilbert by email. Here's what Ed has to say about the database and other topics of interest.

CM: Tell us a little bit about the 10 piece database.

Ed: It's a database which gives the exact win, draw, or loss value of every checkers position having from 2 to 10 pieces with up to 5 pieces on a side. Checker programs have used endgame databases for quite a while. What makes this one somewhat newsworthy is its size and the tremendous increase in playing strength that it gives to Kingsrow. Up until about 2001 the largest endgame database that was available to the public was for 6 pieces. At that time several commercial programs introduced 8 piece databases, and free programs like Cake and Kingsrow soon followed with 8 piece databases computed by Martin Fierz and Jonathan Schaeffer.

The number of checker positions that are possible increases rapidly with the number of pieces on the board, as does the size of these databases and the time it takes to compute them. A 6-piece database can be computed in a couple of hours, and easily fits on a 64mb flash drive. An 8-piece database takes a couple of weeks and occupies about 4GB. It is only within the last few years that anyone has been able to build a 10-piece database. Jonathan Schaeffer was able to complete the first 10-piece database in 2003 using the resources that were available to him as a department head at the University of Alberta. He estimates that it took him 15 computer years to build it. The Kingsrow 10-piece database is the first to be available to the general public.

CM: How long did it take you to develop the database? How did you go about it? What would you estimate you've invested in time and expense?

Ed: I started building it in August, 2004, and finished 11-1/2 months later. Before starting, I spent several months working on the program that would build it and optimizing its performance to run as quickly as possible. I wanted to build the database in one year, and I did not want to buy 15 computers to do it! I also had to work out some technical difficulties in building some of the very largest subdivisions. Schaeffer had available to him a powerful 64-processor Silicon Graphics workstation with 32gb of RAM. I had to work out schemes to build everything on my home PCs with only 2gb. I ended up building and using 4 computers to do most of the database computations. By building them myself I was able to save some money, and also get exactly what I needed, which was computers with lots of RAM and the largest hard drives available, but without any other extras normally purchased with a new PC. I didn't need keyboards, mice, speakers, or displays, since these machines were only used to compute databases 24 hours a day. There is a more detailed account of my building the database at my web site here:

It describes some of the computer science involved, as well as my experiences maintaining the equipment and keeping the whole thing running for a year.

CM: How do you think the database will influence checker play and analysis?

Ed: I think it will help identify some errors in published play, and it will allow many difficult endings that have up to now been left as 'probable loss' or 'probable draw' to be conclusively resolved. Many tournament players like to review their games and see if they missed a win, if their opponent missed a win, or if they lost, identify the exact losing move. The 10pc db is a tremendous help with this type of analysis. There is also a small group of analysts that like to try to find draws in absurdly difficult opening lines. I admit to doing some of this myself, although strictly using the computer, since my own crossboard analytical skills are not very strong. I've been maintaining a specialized 10-piece opening book in which I've accumulated new play in ballots like the Black Hole, Twilight Zone, Gemini, Wilderness, Double Cross, Octopus, etc. This opening book is available on the web here:

CM: Although we know that overall you're won't even come close to making a profit, nonetheless in absolute dollar terms the database is, at $160, a non-trivial investment. What do you think is the market?

Ed: I think the number of people that will purchase this is quite small, due to the declining population of serious checkers players. I will be surprised if the money made from selling 10 piece databases will cover the cost of even one of the computers that I used to build it. This is not a money making business! Selling the database allows me to get it to the people that really want it and can make good use of it. As far as the price goes, I think it's an incredible bargain. If you are serious about playing checkers, there is nothing else that comes close to giving you the information it provides. You cannot obtain one of these anywhere else in the world. If you wanted to build one yourself, assuming you had the skills to do it, you'd have to buy a bunch of computers and run them for a very long time. Then you'd have to figure out how to integrate it into a checkers program, which means you'd have to write your own checkers program...

CM: We understand that the database needs some hefty computing power for effective use. Can you tell us something about that?

Ed: A few years ago this was true, but by today's standards the requirements are no longer "hefty." Basically you need a sufficient amount of RAM to cache portions of the database during a search, and you need enough free hard drive space to store it. That means you need about 2gb of RAM and about 250gb of free disk space. There is a way you can use the database with less; you can read the details at the Kingsrow web site. If you're using an older machine that needs more of these things, it's likely you can add them quite inexpensively. A coworker at the office just bought 2gb of RAM for $75, and 320gb hard drives are selling for around that same amount.

CM: Whenever large leaps are taken in computer checkers, such as represented by your database, there is inevitable discussion of "solving" checkers once and for all. Indeed, a university team is working on that very thing. Do you think checkers will be "solved" and how do you think that might affect human play?

Ed: Apparently Schaeffer is getting close to proving the win/loss/draw value of all of the 3-move ballots. This will be a nice milestone in computer science and the culmination of perhaps 10 years of work by his team. I expect that they will simply confirm what people have already known about the ballots for a long time, and it will have very little if any effect on human play. However there always is a small possibility that they will find a draw in one of the ballots thought to lose. If this occurs then it will be big news for 3-move tournament players, and also for that other group I mentioned that likes to look for draws in absurdly difficult opening lines.

CM: You are a world-class checker programmer and database developer. Can you tell us a little about your background and interests? What do you do as a "day job" and what do you do for fun?

Ed: For about the last 27 years I've been working for what used to be called Hewlett-Packard, until they spun off their electronic instrument business as a separate company a few years ago, and now I work for that company, Agilent Technologies. I work in R&D as an engineer developing new products. I'm married, with 3 daughters, two of whom have finished college, while the youngest just turned 20 and has a couple of years left to go. I do a lot of bicycling on my road bike (on an Italian steel frame that I built into a complete bike about 15 years ago), and I've also been a runner and regular lap swimmer for over 35 years. When I was younger I used to race in running road races and triathlons, and now I keep up these activities simply for the enjoyment and the exercise.

CM: Can you tell our readers how they might decide if they want the database, and how they might obtain it if so?

Ed: If you're serious about the game of checkers, and you want to have the most powerful tool for analyzing positions that is available anywhere, then you want the 10-piece database. All the information that you need to obtain it, including PC requirements and installation instructions, are at the Kingsrow web site:

The Checker Maven thanks database developer Ed Gilbert for granting us this interview, and repeats Ed's statement that if you're a serious checker player, the 10-piece database is a true "must have" product. We're getting our own copy as soon as we possibly can.

Database Creator Ed Gilbert
Photo courtesy of Carol Gilbert

06/16/07 - Printer friendly version
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Ein Feste Burg (A Mighty Fortress)

No, we're not talking about the well-known Lutheran hymn, based on the beautiful aria from J. S. Bach's cantata, BWV 80, "Komm in mein Herzenshaus," although that too would make a wonderful topic if this were other than a checker column.

Instead, we're talking about a "checker fortress" as featured a little while back in Brian Hinkle's challenging Bear Claw problem (click here to review). This problem genre was once treated by Ben Boland (are we surprised?) in one of his many books.

Today, armed with the knowledge gained from Brian's problem, see if you can break into the fortress by solving these three problems. Perhaps you might wish to play some of Bach's immortal music in the background, for the purpose of relaxation, as solving these will be anything but easy.

Problem 1

White to Play and Draw


Problem 2

White to Play and Draw


Problem 3

White to Play and Draw


When you've crashed through the ramparts, click on Read More for solutions, notes, more examples and illustrations, as well as some history on this type of problem.

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06/09/07 - Printer friendly version
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All Ahead Full

A very nice speed problem awaits us this month; it's a situation that looks contrived, but arose in actual play. Good visualization and a firm grasp of tactics will lead you to the solution. It's really easy enough ... but can you get it in thirty seconds? Click below to show the position and to start our no-turning-back Javascript clock. Full speed ahead!

June Speed Problem

Did you get it? Click on Read More to reveal the very pleasing solution.

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06/02/07 - Printer friendly version
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We're Open for Business

The Checker Maven offices have reopened after about three weeks of closure, during which time our weekly publication continued on an automated basis. We're glad to be back to work, and there's surely plenty to work on as we continue to prepare new articles, features, and electronic book editions. Of course, some of our projects have gotten behind schedule but we hope to make up some time over the next little while. Thank you to one and all for your continued readership.

06/02/07 - Printer friendly version
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