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I write, therefore I am

With this variation on a famous statement by the philosopher Descartes, I would like to express that the act of writing about what happens in my life is important to me.

Monday, January 20, 2020


Sunday, January 19, 2020

The Long Way to a Small, Angry Planet

I finished reading the novel The Long Way to a Small, Angry Planet by by Becky Chambers after I started reading it last Thursday, the day I bought the book. It is a long time ago that I read a book in a single go. Yesterday, I had a copy of the second part in my hand when at the American Book Center, but decided to first finish the book, before buying it. The book feels a little like a sitcom, because many of the chapters can be read as a separate story and the order of some of the chapters could be rearranged without hurting the story. (I guess, it would aid making a TV show based on the book.) I have admit that it touched on some interesting philosophical, psychological and social issues.

Saturday, January 18, 2020

Kunstmuseum The Hague

This morning, I went to Kunstmuseum in The Hague to see the exhibition Monet: The Garden Paintings. (If I remember correctly, the previous time, I visited this museum was on March 31, 1977.) There, I saw the following works:
  • White Clematis, 1887.
  • In the Norwegian Boat, circa 1887
  • The Studio Boat, 1877
  • Fishing Nets at Pourville, 1882
  • Rounded Flower Bed, 1876
  • Haystacks: Snow Effect, 1891
  • Water Lilies, circa 1814-1917
  • The Water-Lily Pond, 1889
  • Water Lilies, 1908
  • Water Lilies, 1907
  • Pink Water Lilies, 1897-1899
  • Water Lilies, 1907
  • Water Lilies, 1914-1917
  • Water Lilies, 1916-1919
  • Water Lilies, 1916-1919
  • Water Lilies, 1916-1919
  • The Japanese Bridge, 1918-1924
  • The Japanese Bridge, 1918-1924
  • The Footbridge over the Water-Lily Pond, 1919
  • Irises, circa 1914-1917
  • The Waterlily-Pond, 1917-1919
  • Weeping Willow, 1918-1919
  • House among the Roses, 1925
  • The House at Givery, seen from the Rose Garden, 1922-1924
  • Water Lilies, Reflection of Weeping Willows, 1916-1919
  • Water Lilies, 1917-1919
  • The Path under the Rose Arches, 1920-1922
  • Weeping Willow, 1921-1922
  • The Garden at Givery, 1922-1926
  • The Artist's House, seen from the Rose Garden, 1922-1924
  • Yellow Frises, 1924-1925
  • Wisteria (Study), 1917-1920
  • Wisteria, 1919-1920
  • Wisteria, 1917-1920
  • Wisteria, 1919-1920
  • Quai du Louvre, 1867
  • Roses, 1925-1926
  • Hemerocallis (Daylilies), 1914-1917
  • Water Lilies and Agapanthus, 1914-1917
  • Water Lilies, 1916-1919, pencil on paper
  • Water Lilies, 1916-1919, pencil on paper
  • Reflections of Weeping Willows, 1916-1919

Next, I saw the exhibition about Jeroen Eisinga - The Social Ladder. Several of his films were shown and 'camera' from "The Most Important Moment in My Life" (1995) was on display. After this I went to Chambers of Wonder in the basement, in a certain way the most interesting part of the museum. There I saw the following works:

  • Paul Blanca, Crying (Nora Kimball), 1985
  • Ulay, Woman in bath, 1970-1993
  • Leo Gestel, Recumbent Nude, Seen from the Rear, circa 1909-1910
  • Frederick Linck, Nice boys, 1978
  • Aysel Bodur, Untitled, 1992
  • Wally Elenbaas, Untitled, undated
  • Ellen Mandenmaker, Untitled, circa 1996
  • Ferdinand Hart Nibbing, In the Geul Valley, circa 1904
  • Edgar Fernhout, Zee, 1957

Next, I saw the exhibition Barbara Nanning with works by her. Followed by this, I saw the exhibition Mondrian & De Stijl. I liked the following works, where if no name is mentioned, are by Piet Mondrian:

  • Oostzijdse Mill, 1906-1907
  • Woman in Farmyard, circa 1898-1999
  • View of the Schinkelbuurt, circa 1895
  • Irrigation Ditch with Two Willows, circa 1900-1902
  • Landzicht Farm, (oil study), circa 1905
  • Cows in the Meadow, 1905
  • Flowering Apple Tree, 1912
  • Theo van Doesburg: Composition XVII, 1919
  • Zeeland Farmer, 1909
  • The Red Cloud, 1907
  • Landscape at Evening, 1908
  • Haystack, circa 1907
  • Evening on the Gein, 1906
  • Dredge, 1907
  • Trees on the Gein, 1907
  • Fern near Saasveld, 1907
  • Oostzijdse Mill in Moonlight, circa 1907
  • Mill at Domburg, 1908
  • Evolution, 1911
  • House in Sunlight, 1909
  • Evening; The Red Tree, 1908-1910
  • Aäronskelken (Arum lilies), 1910
  • Junes near Domburg, 1910
  • Dune Landscape, 1911
  • Seascape, 1909
  • Sea after sunset, 1909
  • Composition with Red, Blue, Black, Yellow and Grey, 1921
  • Victory Boogie Woogie, 1942-1944
  • Lozenge composition with Yellow Lines, 1933
  • Theo van Doesburg, Three stained glass windows for doorways in the spangen quarter, Rotterdam, 1919
  • Composition No.3 with colour planes, 1917
  • Composition with Grid 9: checkerboard composition with bright colour, 1919
  • Composition with Grid 3: Lozenge Composition, 1918
  • Composition with Red, Yellow, Black, Blue and Grey, 1921
  • Vilmos Huszár, Composition in Grey, 1918
  • Haystack behind a farm, circa 1902-04
  • A farm shed behind a fenze, circa 1902-04
  • Ditch near the farm landzigt, circa 1900 (drawing)

The last exhibition that I saw was Discover the modern. I found the following works worth mentioning:

  • Leo Gestel, Autumn tree, 1911
  • Jan Toorop, Labour (the woodcutter), 1905
  • Vincent van Gogh, Garden at aries, 1888
  • Paul Signac, Cassis. rap lombord, opus 196, 1889
  • Maximilien Luce, View of the river Schelde, 1894
  • Edgar Degas, Nude study for the little dancer, circa 1878
  • George Hendrik Breitner, Het rokin, circa 1890
  • Pablo Picasso, Harlequin, 1913
  • Charley Toorop, Self-portrait (standing with palette) 1932-1933
I visited the shop of the museum, but did not buy anything.

After this, I visited a number of bookshops in The Hague and Utrecht. In The Hague, I visited: Van Stockum, The American Book Centre, and Paagman. In Utrecht I visited Steven Sterk and Broese. At 18:22, I bought the book Het verborgen brein written by John Bargh, translated from the English Before You Know It to Dutch by Marianne Palm, Aad Janssen, and Nicole Seegers, published by Overamstel Uitgevers in 2018, ISBN:9789048827121, from Steven Sterk for € 7.90.

Friday, January 17, 2020


Thursday, January 16, 2020


I finished reading the novel JPod by Douglas Coupland, which I started reading on November 27 after I bought it on November 14 last year. I bought the book, because it looked interesting with respect to being a kind of epistolary novel with many fragments take from online communications and pages filled with semi-random words and numbers, such as prime numbers and the digits of pi. I did like the novel. I tried to find out if people already solved the many puzzles in the book, such as which non-prime number is inserted in the sequence of prime numbers. The only solution that I found, was in the Master thesis Puzzling translation: Breaking the code by Jonna Verdel, where on page 26 it mentions that the inserted three letter word is EMF.


Monday, January 13, 2020


At 16:57, I bought the book Charlotte van Pallandt: gipsen en schetsen written by Charlotte van Pallandt and Gerdien Verschoor, written in Dutch and published by Hannema-De Stuers Fundatie in 2001, ISBN:9789070842420, from charity shop Het Goed for € 3.50.

Sunday, January 12, 2020

Double date

This year, there will be a lot of special dates. Today is a double date for the notation: DD-MM-YY: 12-01-20. The other special dates of this year are:
  • February 2: Palindrome date (02/02/2020 or 2020.02.02)
  • February 11: Palindrome date (02/11/20)
  • February 22: Palindrome date (02/22/20) and double date (22-02-20)
  • May 5: "Digital" mirror dates (05/05/2020, 2020.05.05, or 05-05-2020)
  • November 2: Palindrome date (02-11-20 or 20.11.02)
  • December 1: Double date (12/01/20 or 20.12.01)

Friday, January 10, 2020

Books, sale and party

At 16:52, I bought the following two auction catalogues published by Christies from charity shop Het Goed:
  • Post-War and Comtemporary Art: Tuesday 1 December 2009
  • Modern and Contemporary Art: 8 December 1993.
In the evening, I went to bookshop Broekhuis for their pre-sale evening for 'friends' of the bookshop. I took almost an hour to look around, but could not make my mind up about buying a book.

Next, I went to PlanetArt, where there was a kind of new years party for all the people who volunteerd for GOGBOT. I arrive around the time of the new moon, which was accompanied with the first, albeit penumbral, lunar eclipse of 2020, which was at maxium at 19:09:59 UTC. I forgot to look up in the sky to see if I could see the moon. I sat downstairs with some tea. Upstairs there was music. Several times, I opened the door for some guests and talked a bit with some. One of them I saw for the third time in three days. I had a good time working on RawParser. I stayed for about two hours.

Thursday, January 9, 2020

The Swarm

I went to the opening of the exhibition The Swarm by Anne de boer at TETEM art space. I arrived a little late and missed the start of the tour. I was not very impressed by the exhibition and the tour.

Wednesday, January 8, 2020

B93 Nu

I went to the exhibition B93 Nu, which was kind of a new year reception, with works from the various artists of the B93 artist collective. I was surprised by the quality of the works on display. I did like the work with the text "bobbinhood" and the words 'be' and 'somebody' in it. I also had a look at the book Saintscape by Claudio Beorchia, which was on display. I saw that the book has an ISBN, which might indicate that there is more than one copy of it. In that case, I would be interested to buy a copy.

Tuesday, January 7, 2020

LISP in C#

Yesterday, someone pointed me at A Lisp interpreter in C# 7. LISP is the third programming languages that I used, after Algol 60 and Fortran. C# is a programming language that I just recently started to use. A long time ago, I made some attempts to program a LISP interpreter in Fortran. Having a lot of programming experience, I thought it would be easy to implement a LISP interpreter in C#, especially, because C# is a garbage collected language itself and in some sense rather close to LISP. I also got the idea to present the implementation is a didactic presentation with comments explaining the code in step-by-step manner. I have created the LISP interpreter in C# repository for this purpose.

Wednesday, January 1, 2020


Tuesday, December 31, 2019

New Years Eve

Because Tuesday is the day that the space of TkkrLab is open for visitors, and usually also the time that most members are visiting, I decided to spend New Years Eve at the space. Someone suggested to order some Chinese/Indonesian food, and I joined in. Several people had brought some oliebollen and drinks. Someone had brought a SodaStream and we produced some carbonated Rooibos thea. As usally, most people did their own thing. Some people played some card games. When one other member exclaimed that he had no idea where to start with Escape room: The Game, I decided to give him some help. After about two thirds of the game, I got bored and another member completed the game with him. I continued working on RawParser. We were not going to see much of the traditional fireworks from the space, from which we have a good view of a large part of the city from about nine meter above ground level, because of the heavy fog outside. Visibility dropped below 100 meters.

Monday, December 30, 2019

'Raw' parser

I remember working on a 'raw' parser during Overkill Festival, 2018. I had several reasons to work on this. I wanted to have a C version of IParse because I came to the realization that C is the most universal supported programming language, the language that is used to implement almost all other programming language (interpretters and compilers) or at least use it to bootstrap it. (IParse was originally written in C.) I also wanted to implement scannerless parsing instead of using a hand-code scanner as in IParse, based on experiments I did with introducing characters sets. During these experiments, I also encountered the need to be more flexable in constructing results of the parsing. IParse has a build-in implementation of abstract syntax tree (or abstract parse tree, as it is called within IParse). This also because I discovered that sometimes you want to deviate the abstract syntax tree from the parse grammar, such as the example of representing array declarations in IDL, which is kind similar to that of C. (As a side note: C# avoided this problem, by having an alternative syntax for declaring arrays.) Furthermore, I had developed a method for defining a grammar in IParse using code, instead of constructing it from a hard coded syntax tree. The idea was to make the parser algorithm agnostic to the data (by using a void pointer) and how it is constructed (by the use of function pointers). This gave me the idea to call it a 'raw' parser. In the past year, I did sometimes have a look at it, but most often I did not enough time to really get into it and make some progress. In the past week, I did set some time aside and also got the idea to make the implementation more self explanatory as a kind of educational tool to explain parsing by adding a narrative in comments. Doing this, already has led some improvements in the code. Interesting. The code can be found in the github repository RawParser.

Saturday, December 21, 2019


At 14:58, I bought the book AKI-jaarboek 2005/06 written in Dutch and English, published by AKI akademie voor beeldende kunst in June 2006, ISBN:9073025087, from Kringloop Enschede for € 1.00. I went to TETEM art space to see the exhibition Should I Stay or Should I Go. I did the Nederlands Gastronomisch Inburgeringsexamen test, but I did not see if I passed of failed the test. Although I am Dutch and should pass the test, I guess, I might have failed, because I do no longer follow the typical Dutch eating habits. The installation Tune of the Hamlets did not work. This installation allows you to mix a choir of people who sing the same song in different dialects of Low Saxon. I also went to photo galery Objektief to the exhibition with pictures by Hessel Bosch, who has been a photographer for more than fifty years. He was present at the exhibition.

Tuesday, December 24, 2019


Friday, December 20, 2019


Thursday, December 19, 2019


This week, it has been warm for the time of the year. Today, the temperature at the airport Twente weather station, reached 15°Celcius, which is a record for this day (but not for this time of the year).


At 17:53, I bought the book De gouden eeuw van Twente: zij die de kunst schonken written by Doreen Flierman and Josien Beltman, in Dutch and published by Rijksmuseum Twenthe in 2015, ISBN:9789072250414, from charity shop Het Goed for € 1.50.

Wednesday, December 18, 2019

The Rise of Skywalker

This afternoon, Annabel and I went to watch the movie Star Wars: The Rise of Skywalker. It has been a kind of traditiong that we go to see the new Star Wars movies on the day that they are released. Although there are tons of so called Star Wars fans who are going to say that this is the worst Star Wars movie ever, for me this one is going to be in the top three. I think this is a very balanced and well directed movie with a believable plot, which places the two previous movies in context and resolve some of the appearant plot holes.


Tuesday, December 17, 2019


Sunday, December 8, 2019

Heliophile and more

I went to see the performance of Heliophile in Haaksbergen. I just missed the start of the performance, because I had left a little late and had to bike against the wind. This was the first performance where the background tracks were replaced with a life performance with a large modular synthesizer. It was also the last performance with Bernard, which means Heliophile will continue as a duo. In the room they were performing, there was also an exhibition of Fotobond Twente. I liked the photographs by Hans Wissink, Marinus Rouweler, and Anja Jalving. When I biked to Enschede, I saw several rainbows (which all originate from the same cloud, I guess). At 14:59. while I was biking on the Helweg, I saw a fragment (left) of a rainbow at the horizon. From 15:10 till about 15:13, I saw a rather bright, double partial (left) rainbow. Then at 15:16, I saw a partial (right) rainbow. It slowly started to rain, while the sun was still shining, and finally, around 15:20, I saw a full, but rather faint, rainbow. I went to Het Bolwerk, where the opening of the exhibition with drawings by Johan Leerkotte. There also were some music performances.

Saturday, December 7, 2019

Groninger Museum

Peter Struycken invited me to visit the Groninger Museum with him, where there is an exhibition of some of his works. After we had some coffee and tea with applepie, we went to the top floor. In the hall we were greated by three of the Boulez carpets, from left to right: Boulez 44, Boulez 27, and Boulez 45e. We sat on a bench and watched ...explosante-fixe... with music by Pierre Boulez and Skrjabins Vision with music by Alexander Scriabin, two 20 minute long animations on music displayed on five large screens. Next we saw the exhibition Presenc by Daan Roosegaarde and the exhibition Mondo Mendini about the Italian designer Alessandro Mendini. At this exhibition, I liked the following works:
  • Schermo for Porro by Alessandro Mendini, 2014.
  • Sinnoso for Maison Matisse by Alessandro Mendini, 2019.
  • (Without title) by Alessandro Mendini, nitro lacquer on wood, 1986.
  • (Without title) by Alessandro Mendini, nitro lacquer on wood, 1990.
  • Photograph of Goetheanum, Dornach designed by Rudolf Steiner.
  • Portret van Alessandro Mendini by Han Meilin, 2010.
  • With suprematistisch huis by Kazimir Malevich, 1920.
  • Stilemi enigmatici by Alessandro Mendini, 2015.
We also saw the museum collection. Of which I liked the following works:
  • Kerkje te Oostrum by Johan Dijkstra, 1922.
  • Meisje aan de pomp by Matthijs Maris, 1872.
  • Mijn atelier by Lawrence Alma-Tadema, 1867.
  • Figuren op het strand by Isaac Israës, about 1925.
  • Jahresteller 1981 for Rosenthal (one of 2500) by Morandini, 1980.
  • Job Hansen by Jan Altink, 1922-23.

Wednesday, December 4, 2019

Kirsen Everink

I went to see the exhibition at B93 with paintings by Kirsten Everink. I have seen many of her paintings at the Finals 2017 exhibition, which means she has not produced many new works in the past two years.


This evening, I finished reading Duin, the Dutch translation of the novel Dune by Frank Herbert. It was my fifth reading of the novel, fourth in Dutch, once in English. The last time, I finished reading the book (in English) was on Sunday, May 8, 2011. What surprised me during this reading, was my emotional responds to it at certain important points. Is this because I am older and have more emotional experiences of because I have become more sentimental. I started to read the book because at the moment, the book is made into a film again (for the third time). I have come to the conclusion it will be very hard to adapt the book and capture the depth of the struggle of Paul, which is so much hidden for the people around him.


Sunday, December 1, 2019

Random maze

In the past weeks, I have been analyzing algorithms to generate random mazes. The kind of mazes that I am studying are mazes within a rectangular grid of rooms where the maze is a spanning tree, meaning that there is exactly one route between each two rooms. In such a maze the number of doors (compared to walls) is one minus the number of rooms. Knowing how many doors and walls there are to be, you can calculate the change that at some position there door and wall. From this you can also calculate the changes for the different types of rooms (with respect to the position of the doors). There are rooms with one door, two opposite doors, two doors with a turn, three doors, and four doors. But it seems rather hard to generate random mazes that match these 'ideal' distributions. Wilson's algorithm is a simple algorithm to generate an unbiased maze. It has almost half the number of rooms with four doors as the 'ideal' maze. I also implemented an algorithm that starting with a balanced random assignment of doors and passages and fixes this by randomly changing passages into doors to connect unconnected rooms and doors into passages to prevent multiple routes between rooms. This algorithm is named 'Random' below. Alternatives of this algorithm, called 'Digging' and 'Trees' below, start with a maze with only walls and only doors, respectively. I also implemented a recursive division algorithm, called 'Spit' below. The traditional depth-first algorithm is called 'Depth-first' in the table below. This table gives for each algorithm the average percentage for the different type of rooms when the algorithm is run 500 times for a 50 by 50 room maze, and also the average distance between every two rooms (with its standard deviation).

               one    opp.    turn   three   four   dist.(dev)
'ideal'     26.69%  13.32%  26.69%  26.65%  6.65%
Wilson      29.18%  17.35%  27.82%  22.18%  3.46%  111.14(12.72)
Random      30.57%  16.15%  26.80%  22.47%  4.01%   96.49(10.20)
Digging     31.70%  15.84%  25.25%  22.79%  4.42%   94.93(11.03)
Trees       30.50%  16.45%  26.78%  22.15%  4.13%   58.50( 1.75)
Split       28.11%  13.97%  32.90%  22.01%  3.01%  123.81(16.30)
Depth-first 10.12%  31.00%  49.00%   9.72%  0.16%  403.49(32.92)

The depth-first algorithm clearly gives a different kind of maze than the other algoritms, resulting in lots of rooms with only two doors and only a very few rooms with four doors. It is obvious that this will lead to a high average distance between two rooms. However, note that the algorithm 'Random' and 'Trees', which are rather similar with respect to the types of rooms they have, yet have a different average distance. The name 'Trees' refers to the fact that the walls grow like trees from the sides, which make that the rooms in the center have short connections to the rooms further away. I have no simple explaination for the fact that the number of rooms with more doors are lower for all algorithms compared to the 'ideal' distribution. I also have not yet found an algorithm that generates mazes that on average are closer to the ideal numbers.


Thursday, November 28, 2019

Has always been dystopia

I went to the opening of the exhibition Has always been dystopia by Erica Ferrari at XPO.

Saturday, November 23, 2019

Overkill Festival: Day two

During the day, I helped as a volunteer at the expo with the VR installations Hana Hana Full Bloom and False Mirror. Later, I looked around and saw Camino Real by Fuckgamedev and Journey to Lavender Town. I also played a little with the modular synthesizer in the synth area. At the start of the evening, I attended a VR music performance by Sonotrope (which I did not find very interesting).

Friday, November 22, 2019

Overkill Festival: Day one

I went to opening of the Overkill Festival, which is this weekend. I watched the modular synth performances by Archeface (recording on SoundCloud) and Jungle of Wires. I also tried some of the VR installations and a game: Hana Hana Full Bloom, False Mirror, Pastoral by Theo Triantafyllidis, The Lacuna Shifts, and VR Wizard: A magical training ground by Power of Moo.

Sunday, November 17, 2019


January 2020
December 2019
November 2019
October 2019
September 2019
August 2019
Alzheimer's Disease
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