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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.

Saturday, February 22, 2020

Palindrome and double date

Today is a palindrome date when the date is written in the format MM/DD/YY: 02/22/20. It is also a double date for the format DD-MM-YY: 22-02-20. This is the fourth special date of this year.

Thursday, February 20, 2020

25 years

Today it is 25 years ago, that I wrote my first entry in this online diary. I was not one of the first to start an online diary, but I wonder how many of them are still writing them. One of them, Carolyn L Burke, already stopped many years ago.


I went to TETEM art space for the opening of the exhibition BodyBuilding (info in Dutch) developed by the Hackers & Designers collective with the following people: It is an interesting exhibition. Finding the right balance between an exhibition being self-explainatory and dealing with complex matters that can not be grasped immediately. At 17:12, I bought the book On & Off the Grid edited by Genevieve Costello, written in English and published by Hacker & Designers in 2017 from then for € 15.00. The back of the cover has the text: "Printed with conductive ink the cover of this book functions as a controller for layouting."

Wednesday, February 19, 2020


Sunday, February 16, 2020


The record temperature of 17.4°Celcius at Twenthe Airport (beating last years record of 14.1°Celcius) was reached at the start of the evening. These high temperatures where caused by Storm Dennis, which pulled warm air from the South. Around seven, a strong cold front passed with a lot of rain, causing the temperatures to drop about eight degrees within ten minutes.

Saturday, February 15, 2020

Picasso & Matisse

Conny and I went to the Rijksmuseum Twenthe to see the exhibition Picasso & Matisse. Beauty is a line. I found the following works worth mentioning:
  • Henri Matisse, Arabesk, 1924.
  • Henri Matisse, Naakt in stoel, voor Maskrabiya, 1925.
  • Jan Sluijters, Halfnaakt (vrouw van de schilder), circa 1912.
  • Charley Toorop, Dame in Avondtoilet.
  • Henri Matisse, Liggend naakt met fruitschaal.
  • Pablo Picasso, Vrouw met halsketting, 1947
  • Constant, Eivormige constructie, 1957
  • Rosemin Hendirks, Zonder titel., 1997
  • Pablo Picasso, Balzac, 1952
  • Henri Matisse, Marguerite II
  • Pablo Picasso, Zittend naakt, het hoofd ondersteund, 1934.
  • Pablo Picasso, Schilder en breiend model, uit Le Chef-d'oevre inconmu van Honoré de Balzac, 1931.
  • Pablo Picasso, Klein vrouwen hoofd met bloemenkroon, 1962.
  • Charley Toorop, Zelfportret met wintertakken, 1944-1945.
  • Henri Matisse, Naakt met ster, 1938
  • Henri Matisse, Primavera.
  • Jan Toorop, Spiegellijst (Adam en Eva) uitvoering M. Joosstens, 1898.
  • Jan Sluijters, Larens landschap met oktoberzon, 1910.
  • Toon verhoef, Holland Festival, 1988.
  • Henri Matisse, De lagune I, plaat XVII, uit Jazz, 1947.
  • Pablo Picasso, Bachenaal II, 1959
  • Piet Ouborg, Arabesk, 1943.
  • Henri Matisse, Naakt voor Cleverland, 1932.
  • Constant, La fleur mèchanique, 1959.
  • Ernst Ludwig Kirchner, Danseres in stoel, circa 1908.
  • Zoro Feigi, Hula, 2016.
  • Pablo Picasso, De Stier, 1945-1946, series of eleven.
  • Jacoaba van Heemskerk, Compositie, 1917.
  • Jan Sluijters, Opkomende bui bij Heeze, 1909.
Next we walked through the exhibition Berlin Geisterbahn with photographs by Fons Brasser. I took some pictures on the maps of the S-Bahne which were on display. Next we saw the exhibition with works by Ben Akkerman. I liked the works:
  • Untitled, 1973-1975.
  • Untitled, 1993-1995.
  • Untitles, 2002.
  • Untitles, 2002-2004.
From this we walked through the exhibition with works from the collection and went to see the exhibition Onzalige bossen - Onzalige tijden with drawings by Geert Voskamp. I liked the works:
  • Politici & Terrorist
  • Strijdtoneel (1 en 2)
  • Duivelsstenen
  • Bosbeelden (6x), 2018
Finally, we saw the exhibition Ars longa, vita brevis. Although, I walked through this exhibition many times, walking through it with Conny made me see works that I had missed the times before, because she made me pay attention to them. So, it is always worth to go see some again with some one else. We completed our stay at the museum with some sausage roll with some tea.

Friday, February 14, 2020


Thursday, February 13, 2020


At 17:59, I bought the book Spirits of Internationalism 6 European Collections 1956-1986 written by Anders Kreuger, Joram Kraaijeveld, and Steven Ten Thije, written in Dutch and published by Van Abbemuseum Eindhoven in 2012, ISBN:9789490757069, from charity shop Het Goed for € 1.50.


Tuesday, February 11, 2020

Palindrome date

Today is a palindrome date when the date is written in the format MM/DD/YY: 02/11/20. This is the third special date of this year.

A Closed and Common Orbit

This evening, I finished reading the novel A Closed and Common Orbit by Becky Chambers. The novel is placed in the same universe as The Long Way to a Small, Angry Planet but it not a real continuation of the story, because the main characters in the first novel do not return in this novel. I understand that the third novel is again about different persons. I guess that there would have been room to let some of the characters of the first novel return in this second novel. This novel, much different from the first novel, reads more than one (actually two) story than like a collection of more independent stories. The first half is a little slow.

Friday, February 7, 2020

C# generics and class extensions

I have been programming in C# for some time now, and I am beginning to appreciate the language more and more. I often use a Dictionary class for collecting information about certain items. When you found an item, you want to know if you already collected some information with the item, and if not you want to add an empty record with said item, to store the information. The Dictionary class does not have a method for doing this. Using generics, I wrote a derived class with the method. But than someone suggested, that you could also implement it as a class extension. It took me some time to figure out how to specify the constraint that the class for the 'value' of the Dictionary class has a default constructor: after the header of the method with where V : new(). The final result became:
public static class DictionaryExtensions
    public static V GetOrAdd<K, V>(
             this Dictionary<K, V> dict, K key)
                  where V : new()
        if (dict.TryGetValue(key, out V value))
            return value;
        V newValue = new V();
        dict.Add(key, newValue);
        return newValue;


Thursday, February 6, 2020


I went to Rotterdam, where there is Art Rotterdam Week. At the Rotterdam Tourist Information located in the central station, I got the free Art Rotterdam Week map. I went to the exhibition TECART - Quantum Supremacy, which is organized by PLANETART, which also organizes GOGBOT. The exhibition is smalller than GOGBOT. I liked the following exhibits: I went to Doppio Expresso and had some 'White Czar' tea: "Pai Mu Tan" white tea, bergomot, mandarin, vanilla, rose petals. On the way back, I took a picture of the new depot of Museum Boijmans Van Beuningen. At the entrance of the road to TECART, I had a second look at a replica of the DeLorean time machine from Back to the Future. I walked through the city. At 15:17, I bought the book Energieen edited by Wim Beeren, Frits Keers, and Din Pieters, written in English and published by Stedelijk Museum in 1990, ISBN:905006034X, from De Slegte Rotterdam for € 20.00. I also went to bookshop Donner. I took the train home and made a stop in Utrecht, where I visited the bookshops Steven Sterk and Broese Boekverkopers. At 19:19:36, I bought the book How to f*ck a woman: leer van een vrouw wat vrouwen willen written by Ali Adler, translated from the English How to F*ck a Woman, an Insider's Guide to Love and Relationships into Dutch by Margot Reesink, published by Gottmer Uitgevers Groep in 2016, ISBN:9789401302753, for € 7.90 from the latter one.

Wednesday, February 5, 2020


I recieved the book Origami for the Connoisseur written by 笠原 邦彦 (Kunihiko Kasahara) and Toshie Takahama, written in English, translated from 折り紙超難解マニア向き作品集 in Japanese, published by Japan Publications Inc. in 1987, tenth printing from September 2007, ISBN:9784817090027, from 'Boekhandel Louis Tinner - Maurice Janssen' for € 8.00. On page 58, the book presents The HK Cube, or Trick Dice, a design attributed to Kunihiko Kasahara and 芳賀和夫 (Kazuo Haga). I also found this independently: How to fold a cube from a square sheet.

Arts N Beats

I went to the opening of the exhibition Arts N Beats with black light art by Henna Khemai and music by Kids w/K at B93 artist collective.

Sunday, February 2, 2020

Universal palindrome date

Today is a palindrome date when written like 02/02/2020 (MM/DD/YYYY) or 2020.02.02 (YYYY.MM.DD). The previous such date was November 2, 2011, which is 3014 days ago. It is also palindrome data when written in like 02-02-2020 (DD-MM-YYYY). The previous such date was February 21, 2012, which is 2903 days ago. This makes is a universal palindrome date of which there are only twelve. The previous such date was November 11, 1111, and the next will be December 12, 2121. Note that this is also a "digital" rotation date, which means that if the date is written on a seven-segment display it looks the same when rotated over 180° This is a subset of the palindrome date that are made up out of the digits 0, 2, 5, 6, 8, and 9. It is the first for the formats MM/DD/YYYY and YYYY.MM.DD and the second for the DD-MM-YYYY format. This is the second special date of this year.

Saturday, February 1, 2020


I went to see some exhibitions in the city. First, I went to photo gallery Objektief to see the exhibition Voor Orhan / Voor Fernando. Quite intereseting, not only the photographs, but also the subject and the materials used. Next, I went to Concordia, where I saw Monument Levenslicht by Daan Roosegaarde, which is part of a larger project.

Friday, January 31, 2020

12.3° Celsius

The previous weather record for the maximum temperature at Airport Twente for this date, was 12.1°C in 1990. In the evening, between eight and nine, a temperature of 12.3°C was recorded. It would not surprise me if the lowest temperature of 9.4°C is also a record. During this time of the year, the average maximum temperature is 5.2°C. I have not seen any snow yet, not even wet snow. Some snow did fall in the North and South of the country. We also did have no serious freezing periods.

Thursday, January 30, 2020


At 18:07:02, I bought the book A Closed and Common Orbit written by Becky Chambers in English and published by Hodder & Stoughton in 2017, ISBN:9781473621473, from bookshop Broekhuis for € 12.99.

Monday, January 27, 2020


Saturday, January 25, 2020


Today is the first day of the year of the rat according to the Chinese calendar. The spring festival has begun. I wish everyone, and especially all people in China, a very healthy New Year in view of Wuhan coronavirus outbreak. (The genome of the Wuhan-Hu-1 virus just encodes for ten genes, producing ten different proteins. One of the ten gene takes up almost twothirds of the genome. It would not surprise me if this is the gene for the 'evil' protein, which allows the virus to enter the human cells and gets itself replicated by those cells.)

Tuesday, January 21, 2020

Volume irregular hexahedron

One way of calculating the volume of a hexahedron is to divide it into six (or five) tetrahedron for which there is a 'simple' formulea to calculate the volume. Another method consists of calculating the volume is to divide each side in two triangles and calculate the volume of the tetrahedron made of the triangle and an arbitrary point (usually the origin). This works as long as the sides are flat. But when the four points of a side do not lay in a plane, there are two ways to divide it into triangles, which result in a different volume. So, the volumne is not really defined in this case. One approximation is to take the average of the two ways. This can be done by adding half of the volume of the tetrahedron between the four corner points. If the four points are in a plane, the volume of this tetrahedron is zero. I have no idea if this approximation is the same as defining the volume when taking the curved surface between the four edges that is made out of straight lines connecting the edges at 'equivalent' distances, kind of simular to the hyperbolic paraboloid.

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, 2020.02.02, or 02-02-2020)
  • 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


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