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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.

Friday, April 19, 2019

Two books in cassette

At 13:09, I bought the book Ovidius Metamorphosen - Munkedals Voorbeelden (two books in a cassette) with a forword by Nova Rese and part of the Dutch translation by M. d'Hane-Scheltema of the text Metamorphoseon libri by Ovid written in Latin, from charity shop Het Goed for € 7.50.

Thursday, April 18, 2019

Decentralized web

I went to a presentation about the decentralized web given by two people from Muze, the developers of SimplyEdit (the first CMS designed for the decentralized web) and SimplyView. The decentralized web is seen as a solution for linkrot, congestion (also due to DDoS attacks), and vendor lock-in. It does not solve problems with privacy and control. The decentralized web is not the same as blockchain, although some implementations make use of blockchain technology. The centralized web is based on peer-to-peer node networks. This makes the browser into a server as well. More and more often the browser is becoming the OS, which is, for example, seen in the development of progressive web applications. Some decentralized web technologies are:


I saw the exhibition Windstilte with works by Manje Dijkman at Bookshop Broekhuis. The exhibtion contains portrets but also some landscapes consisting of two pannels, where the top one represents the sky. I saw the exhibition Living Landscape by Marloes Staal at XPO. The guests where sitting outside because of the nice weather and I talked a bit with some of them.

Bioart's engagement with life

In the evening, I went to Tetem artspace for the talk/workshop Bioart's engagement with life by Lotte Pet. She is an artist, studied art and now doing an PhD in which she researches art as a means to gain knowledge within scientific and technological discourse. (The following is based on notes I took during the talk.)

Biotechnology is the manipulation of living organisms or their components to produce usefull usually commercial products. Currently, a lot of research is done with applications to health care. But there are also big ethical issues involved. Biotechnology is not neutral. The application of it has an impact on our culture and how we value things. It changes our opinions. A recent example is story of two Chinese babies, whoes DNA was modified with CRISPR/Cas9 in order to make them resistent for HIV. But it also might have improve their intelligence. Should we improve humans? Does increasing intelligence improve humans? But also direct-to-customer genetic testing has implications. The cheapest form is genotyping: telling you something about your ancestory. Another form is whole-genome sequencing, which allows to find for genetic defects that are associated with certain health risks. And than there are also issues with the storage of DNA profiles, which could be used for other purposes. Take, for example, the case of the Golden State Killer. (I made a remark about the impact of prenatal testing.) In the end it all comes down to the question: What does it mean to be human?

BioArt is a contemporary art practice started late 20th century. There are two means: Representational tactic (art presenting the results of the application of biotech) and presentational tactic (art created through the application of biotech). Goals of BioArt could be: Involvement with living matter, exposes hidden emotions and values, demystifies science, public empowerment: enables being otherwise, and/or just focus on methods itself. Artistic skills that are involved are: Irony (Dove d'Or), appropriation (Eduardo Kac, GFP Bunny), rule-breaking (Jennifer Willet, BIOplay), flip-thinking (Chrissy Conant, Chrissy Caviar), identification/objectivication (Tissue Culture & Art project, Victimless Leather: A Prototype of Stitch-less Jacket grown in a Technoscientific 'Body').

At the workshop part, we tried to extract our DNA from saliva using table salt, detergent, lens cleaner liquid, and alcohol. I put the results of my extraction in a small glass bottle. A picture of this is displayed on the top. I am not sure whether this is only DNA, because I might have poured in the alcohol too fast.

Wednesday, April 17, 2019


At 10:48:07, I bought the book Finnegans Wake written by James Joyce in English and published by Penguin Adult in 2000, ISBN:9780141183114, from charity shop Het Goed for € 3.50.


I installed and tried out Meshroom on my set of plant pictures. For open source software, the interface looks good. One of the steps, requires a CUDA (2.0) compliant NVIDIA graphics card. There is a work around, but it results in a lower resolution mess. I have to figure out how the graphics viewer works. I understand they have a plug-in for Maya.

Monday, April 15, 2019


Saturday, April 13, 2019

Tegelreliëf Ad Dekkers

I was invited for the opening of Tegelreliëf Ad Dekkers, a tile relief designed by Ad Dekkers measuring 9 by 18 meters, which was recreated at a park in Bergeijk after it had to be removed from a school in Gouda to make room for buildings. The offical opening was performed by Beatrix of the Netherlands, who knew Ad Dekkers from the meetings she and her husband organized between 1968 and 1975 on Drakensteyn Castle. It is said that she was rather fond of Ad Dekkers. She had one of his sculptures placed in the garden. When they moved to Huis ten Bosch Palace she asked Ad Dekkers for another copy of the sculpture to be placed there. I met with Peter Strucken, who was a good friend of Ad Dekkers. I briefly greated Daniel, the son of Ad Dekkers. I also shaked hands with Rudi Fuchs. I talked a lot with Carel Blotkamp, who also gave one of three introduction talks before the opening of the tile relief. After the official opening, I visited the exhibition about Ad Dekkers. When leaving, I received a goody bag with the books:
  • Louis van Roode: meester in monumentaal maatwerk written by Willem Heijbroek in Dutch and published by De Vrije Uitgevers in 2015, ISBN:9789082453904.
  • Rietveld's design factory re_newed written by Toon Lauwen in English and Dutch, and published by Aerial Media Company B.V. in July 2017, ISBN:9789402602555.

Thursday, April 11, 2019

Be Your Own Robot

I went to the opening of the exhibition Be Your Own Robot by Sander Veenhof. The following are the notes that I took during the artist talk during the opening (with links added later):
    It ia about augmented reality. How does it work in the real world. What is it really about? What do I, as an artist, with it? He started long ago with a Commodore 64. He created Biggâr, the largest virtual art work in the world. In 2010, he made WeARinMoMA. 2011. A virtual traffic light at Oerol. People look a lot at their smart phones. Project Meet your stranger. Now it is called leesluid.nl. Pokémon Go. Google Glass. He (re)created a screen saver for it. Slowly all arguments again augmented reality are disappearing. A virtual glass is looking all the time with you, through the cameras. The idea of virtual fashion. Google now has a patent on making the love gesture for liking something now. He created a patent alert app for augmented reality. The App Store Review Guidelines are quite restrictive. There seems to be not much room for art. All tech companies what you to put on these kind of glasses, because they follow what you see. Companies life Facebook are interested in this information. In the past he often was in Second Life. Now it is almost empty. There you can buy all kind of things to improve your appearance and behaviour. The same thing might happen with AR glasses. He created some apps to make people think about what could happen in the future. The woordenjutten AR app. You could create theather in which people become the actors. With IF _THIS_ THEN I, you can create some rules for yourself. So the answer is: Be Your Own Robot

Tuesday, April 9, 2019


Sunday, April 7, 2019


It was sunny today, with a maximum tenperature of 20.7°C at the official weather station, and the back garden was filled with the smell of our magnolia, which is full of flowers now. Some flowers are already dropping their leaves but there are still some buds that have not opened yet. I am happy that this year I can enjoy the magnolia such a long time. I got the impression that in other years it was over sooner.

Saturday, April 6, 2019

Warhol - The Biography

I finished reading the book Leven en dood van Andy Warhol, the Dutch translation of Warhol - The Biography by Victor Bockris, which I started reading on December 1, shortly after I finished reading The Trip. I bought the book on May 4, 2014. Bockris is quite enthousiastic about a, A Novel and gives some interesting background information. Although the biography contains a lot of details, I did not get a consistent picture of Warhol, which is probably also due to his complex personality.

Booster festival

In the evening, I went to the Booster Festival. In "De Generaal", I found an interesting tile pattern, which is shown on the picture. Later, I concluded it is the clasical Versaille tile pattern. I went to "De Grote Kerk" (the old church) and did some programming, while listening to "GREBE". During the sound check of Vera Bon, I decided to walk to the front. I enjoyed the performances and afterwards, I bought their first EP, which was just released afterwards. Later, I also listened to a performance by The Black Fall and also bought their CD. At last, I went to the Official Unofficial After-Party. I met some friends outside waiting for the door to open. The Rave party was in the attick. I did not stay long and took one of the leaflets on my way out.

Wednesday, April 3, 2019

Observation of thinking

In the evening, I went to the opening of the exhibition Observation of thinking with works by Ray Andreas, which consisted of painting, litho prints, and creamic tills, all around the same theme. I talked some time with him about our shared experiences.

Sunday, March 31, 2019

Lecture, exhibitions, and books

This afternoon, I went to the lecture Het naakte lichaam en zijn sluier (The naked body and its veil) by Ger Groot, a Dutch author and philosopher at Rijksmuseum Twenthe, which was given in the context of the exhibition De Naakte Waarheid, which I visited on the second of this month. Most of the people were above my age. During the lecture several nude images, some of them almost pornographic, were shown, while the lecturer explained that it is almost impossible to look at the naked body without it elicting emotions, often of an erotic nature. When presented with a nude image, our eyes search for genitals almost automatically. It is difficult to be objective. We have a body and we are a body. He stated that science, asking the how, while ignoring the what, is in a sense the opposite of pornography, which deals with the what, while ignoring the how. We often switch between the scientific, rational way of looking from the enlightment and the romantic view, but that the latter often wins. The body remains itself. He showed several images from artworks from the exhibtion and when I watched the exhibition again, I looked with different eyes. I was especially touched by the drawing Paring (Intercourse) by Aat Veldhoen. I also noticed the Dutch translation of the quote The question isn't who is going to let me, it's who is going to stop me ascribed to Ayn Rand on the wall with the most pornographic pictures of the exhibtion, three pictures from the A History of Sex series by Andres Serrano. At 15:05:01, I bought the book De Naakte Waarheid edited by Doreen Flierman and Thijs de Raedt, written in Dutch, published by the museum in 2019, ISBN:9789462622296, from the museum shop for € 19.95.

I also went to the exhibition Graduates 2018 at photo gallary Objektief with pictures by Christine Mooijer from the Soliloquy series, Marvel Harris, Yasmilla van Vliet, and Romina Demy.

At 16:51:54, I bought the book The Favourite Game written by Leonard Cohen in English, republished by by Blue Door in 2009, ISBN:9780007318391, from bookshop Broekhuis for € 5.00. I got the book Jas van belofte written by Jan Geurt Siebelink in Dutch and published by Stichting Collectieve Propaganda van het Nederlandse Boek in 2019, ISBN:9789059654679, for free as part of the Boekenweek.

Saturday, March 30, 2019

TkkrLab open day

Today, was the yearly open day of the Dutch hackerspaces. I arrived at the TkkrLab space shortly after ten in morning and left after midnight. We had about twenty visitors and I did some guided tours and showed some of the projects I have been working on in the past years. Annabel also came and we spend some time thinking about the puzzles she is developing. I also donated my Teco VA120 terminal to the space to be used for the new bar system.

Friday, March 29, 2019


When I went into the back garden this afternoon, I smelled the nice fragrance of our magnolia. About half of the flowers had opened. It very much like spring and it made me happy.


Thursday, March 28, 2019


In the afternoon, I went to Amsterdam with the intention to go to get some more information about the Post-Wat & Contemporary Art auction, but it turned out that the went to the wrong place. Afterwards, I visited the bookshops Het Martyrium and Scheltema but I did not find anything interesting enought to buy.

Saturday, March 23, 2019

Learning Chinese

Because we have plans to make a trip to China this year, I have decided to learn some Chinese. I have installed the ChineseSkill Android app and finished some of the basic lessons, but since this morning, I get a message that I am out of pandas and I have no idea how to get more. Maybe because I have no payment method installed. Maybe I have to take a look at some other Android apps. I am also thinking about making my own flashcards and go over them when I bike to my office or listen to language learning mp3's. I found the video 200 Chinese Phrases for Beginners from the Learn Chinese 360 YouTube channel, which seems to be an interesting starting point to improving listening. This morning, I also started reading the Dutch book Het karakter van China (known in English under the title China: Empire Of Living Symbols) by Cecilia Lindqvist, which might be a good way to learn Chinese characters.

One flower

At the end of the afternoon, one flower of our magnolia had opened a little. Expect that many more flowers will open in the coming days.


Early this evening, I bought the drawing Bikerider from Maria Britze after her exhibition Colourtramp at B93 came to an end today.

Wednesday, March 20, 2019


Yesterday evening, I made some modification to my Exact Cover program, such that it can be used to estimate the number of solutions of the Octopuszle. This morning, I made some modifications of the program. The idea of the 'sample' mode is that it will run for two minutes using a random selection of vectors from the column with a minimum value of vectors. While doing so, it measures the distance of the solutions spaces that has been covered under the assumption that each selection covers an equal part of the solution space. It also counts the number of solutions that were found. These two can be used to estimate the total number of solutions. However, the assumption is not correct and does influence the result. This morning, while biking to my office, I realized that there is an easy way to estimate an upper limit on the estimation. There are 256! ways of putting the pieces within the 16 by 16 square. Now, what is the chance that all pieces fit. There are a total of 2.(2.162-16.15) + 2.(2.162-152) relationships that have to meet. If we assume that all the chances are independent, which is probably not the case, than the number of solutions are about 2.409128076060726988778E+170 (found by calculating the expression 256!/(2^(2*(2*16*16-15*16)+2*(2*16*16-15*15))) with Keisan Online Calculator. I have no idea which statisical method I should use to look at the numbers produced by the sample mode, but if I just have a look at the numbers, it seems to return a number around 10163 solutions. This is close to the theoretical maximum number of solutions.

Saturday, March 16, 2019

Exhibitions and book

I went to XPO to see the exhibition A Blue, A Purple, Aloë vera, Aster, Banaan, Cupcake, Engeland, Hibiscus, Pilli Pilli, Prinsessen Roze, Selectie and Ultiem by Evangeline Clark. She was there herself and I talked a little with her. I think about buying Pilli Pilli. Next, I went to bookshop Broekhuis, where at 16:08:40, I bought the book De edele kunst van not giving a fuck written by Mark Manson, translated from the English The Subtle Art of Not Giving a F*ck into Dutch by Annoesjka Oostindiër and Henk Popken, published by Bruna Uitgevers in 2017, ISBN:9789400509023, for € 20.99. I walked through the city and went to have a look at the exhibition Monsterproject at Concordia. In a bookshelve, I discovered a copy of Jaarboek 09/10. I made some inquiries as to if it was on sale, but it was not. I did get some tip about another place where the AKI yearbooks can be found.

Octopuszle solutions

A large part of the day, I worked on a program to generate an exact cover problem for solving The China Labyrinth within a more compact, hexagon shaped, enclosure. As usual, a one off error, was the last bug that kept the program from running. Below one of the solutions is given.

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I noticed how this solution consists of three parts (counting the empty piece as a separate part), and it only has one loop (circling the empty piece), which seems to be a counter example of the statement that I quoted yesterday. Maybe the proof is not as solid as it was thought. Because there are so many solutions to the puzzle, I thought that maybe an algorithm that would search for solutions at random would give a more varied number of solutions. When I started working on this, I discovered a bug in the algorithm, that was introduced when I did some experimentations on reducing while solving. When I fixed it, the program returned many solutions per second. I decided to also give it a try at Octopuszle and for that too it produced many more solutions than before. Below ten random solutions are given.

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Friday, March 15, 2019

The China Labyrith

While thinking about better ways to solve the Octopuszle, I decided to take one of the diagonals away, and try to fit the 64 remaining pieces into a 8 by 8 grid. Even then, the program did not find many solutions per hour. I let the program run some time until it found 1900 solutions. I did think about some ideas to find more solutions. I did realize that the remaining puzzle was actually The China Labyrith inside a rhombus. After realizing this and remembering the statement: "It was soon discovered and proven that the number of seperate groups (the blank counting as one group) will always equal the number of loops (holes in the solution)", it became clear to me that one of my approaches to find more solutions, was never going to work. Also it is clear that the one piece with no lines, cannot be at the edge, but must always be in the middle. This evening, I worked at the visualization of one of the solutions, also to verify that my mapping to an exact cover was actually correct. The visualization uses one of the lines generated by the exact cover algorithm.

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Saturday, March 9, 2019


At 15:58, I bought the book Science * Art written by Ans van Berkum and Tom Blekkenhorst in English and published by The Fentener van Vlissingen Fund, ISBN:9789090013596, from charity shop Het Goed for € 2.50.

Magnolia seed

This morning, I noticed that some of the outer shells of the flowers of our magnolia had cracked, a sign that it might start flowering within some weeks, which would be rather early this year. I decided to have a look at the one seed that I had discovered last year and kept in our shed, only to discover that it was covered with mold. In the afternoon, told Annabel about. She went to inspect the magnolia and discovered two other withered pods that had contain one or two seeds. Annabel noticed that it is not so difficult to grow a magnolia from a cutting. I told her, that I rather grow one from a seed. This fall, I will look more carefull for seeds and hopefully treat them better.

Friday, March 8, 2019


Wednesday, March 6, 2019


April 2019
March 2019
February 2019
January 2019
December 2018
November 2018
Alzheimer's Disease
Trip to China 2019
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