Monthly Archives: September 2015

Bongard problems (1)


The Russian scientist M.M. Bongard published a book in 1967 that contains 100 problems. Each problem consists of 12 small boxes: six boxes on the left and six on the right. Each of the six boxes on the left conform to a certain rule. Each and every box on the right contradicts this rule. Your task, of course, is to figure out the rule.

Here is a trivial example:
Bongard problem 2015-09-15 nr 2 exercise

Here is something more resembling a puzzle:
Bongard problem 2015-09-15 nr 1 exercise

You can check your solutions here

You can find more Bongard problems at Harry Foundalis site, and I intend to publish more problems in the future.

Vinken – Checks


One of the leading puzzle publishers in the Netherlands, Sander Puzzels, recently came up with “Heggies en Vinken”. It introduces two new puzzles types, “Heggies” (which I suggest to translate as Hedges) and “Vinken” (translated in this post as Checks). Both are invented by Ron Mentink.

Though Heggies is probably the more interesting, in this post I would like to concentrate on Vinken/Checks. I hope to review Heggies / Hedges in a later post.

In Checks puzzles, a 9×9 grid is given. Every row and every column contains exectly 3 Checks, which are never horizontally or diagonally adjacent. Some of the empty locations have been marked with an X, and it is your task to deduce where the Checks are located.

Puzzle 1
Vinken 2015-8-23 exercise nr 1

Puzzle 2
Vinken 2015-08-25 nr 2 exercise

Puzzle 3
Vinken 2015-08-23 nr2 exercise

Personally I found it a reasonably nice puzzle. One drawback is that all clues are horizontal or vertical, with no combinations of the two clues. That is, I have been unable to come up with any situation which can only be solved with a combination of a horizontal and a vertical clue, and not with just one of them. I think there is room for improvement on this puzzle design.

If you like this puzzle or not is probably a matter of taste. If you like it, you may want to mail order some (no, I dont get a commision). At the moment I write this there are 2 issues available in their webshop. Though the website is in Dutch, and the rules are in Dutch, and the magazine is in Dutch, the ordering process should be fairly straight forward, and settng the language in Chrome should be sufficient. The puzzles can be made without any knowledge of Dutch.

You can check your solution of puzzle 1 here

You can check your solution of puzzle 2 here

You can check your solution of puzzle 3 here

Update November 28, 2015:
In issue 4, the publisher increased the difficulty level and I like this 🙂
Much better now.