Leiden, March 22nd 2019
Dear Dr. Julien, 
Following up on the previous letter in which I introduced myself as well as my interest in your photographs, I would like to share some thoughts with you about the way you and I manoeuvre between – and make use of different disciplines. Pointing out some of the similarities and differences between us will, hopefully, explain what I started to do with your photographs and why.  
I’ll take the academic disciplines we wish to engage in and our dissertations as vantage points. It seems to me that we both are primarily interested in anthropology. This is not the most obvious academic discipline for either one of us, taking into consideration that your doctorate, as I only recently found out when trying to read your dissertation, was obtained in ‘math and physics’ at Utrecht University and mine in a programme for artists and designers offered by Leiden University. We both start our inquiries with multiple disciplines at play. The question then is how these disciplines related or relate to each other. 
In academic discourses across the humanities and social studies the word ‘interdisciplinarity’ is currently ‘en vogue’. The term, signifying “the combining of two or more academic disciplines into one activity”, usually implies something that is desirable and productive, but how and when the drawing of knowledge from several fields or disciplines into one particular context actually leads to added value, to a whole that is more than an (often unequal) accumulation of its parts, is rarely clear and I have not yet seen it addressed in a satisfying way. In an attempt to address this in relation to our practices I would like to first give some thought to the two components of the notion: ‘Inter’ and ‘disciplinarity’.
The word disciplinarity builds, of course on discipline, which can signify both a distinct subdivision of knowledge as well as “the practice of training people to obey rules or a code of behaviour”. Building on these two meanings disciplinarity is a framework that allows specialised discourse to unfold and a factor that limits the exploration of possibilities through rules and codes. 
The prefix ‘inter’ signifies an in between. Alternative prefixes in relation to disciplinarity are intra- (within or inside), multi- (involving several or many disciplines), cross- (beyond disciplines, combining disciplines) and trans- (the union of interdisciplinary efforts).
Besides it may not be bad to take into account that to ‘inter’ as a verb signifies the activity of burying a dead body, as it might have to lead to the conclusion that to go from disciplinarity to interdisciplinarity implies the end of the relevance of the subdivisions of knowledge involved. On that note I’ll return to the ways in which each of us was disciplined.
Knowing that you taught chemistry in a high school for decades, I was surprised to learn that you were awarded your doctoral degree not in chemistry but in math and physics. When I was in high school the three were distinct subjects. It did not occur to me then how they relate, overlap and need one another, and I guess I have not given it a lot of thought since. A confession: I hated math and physics even more than chemistry and dropped all three subjects as soon as I could. I (therefore?) do not understand most of the writing in your thesis. It is presented in jargon that is only accessible for those who have been disciplined. 
I tried to understand the title of your dissertation “Electrokinesis of Silverhalogens” by looking up the two words that meant nothing to me on first sight.
About electrokinesis I read that it refers, in physics, to “the transport of particles or fluid by means of an electric field acting on a fluid which has a net mobile charge.” This still had a limited resonance, but the word electrokinesis also signifies the idea of the generation of electrical force using psychic power, as ‘demonstrated’ in works of fiction. I stumbled upon numerous sources that claim that this type of electrokinesis can be trained by humans. What do you think? Does this border on the many myths you heard in Africa? Is it simply an appealing story? Something we are yet to understand and master? Or can choose to believe (in) it, like the existence of one superior being and creator, as you so often discussed with your friends belonging to pygmy communities?
The title of my dissertation is “Ebifananyi, a study of photographs in and through an artistic practice”. I imagine that there is one word in this title that does not mean anything to you. Or, actually, could the Luganda word Ebifananyi ring a bell and take you back to the time you visited Buganda and photographed the royal enclosure and tombs in 1933? In any case, Ebifananyi is the word used to signify photographs as well as other two-dimensional referential depictions, but its most literal translation would be likenesses. This suggests that photographs are something different for people who use this linguistic construct than for you and me, who have been disciplined to think of them as pictures made with a camera and a light sensitive surface. This is funny when realising that until recent developments in digital photography, the silver halides among the silver halogens you studied were, as you of course know, key to the production of photographic pictures. 
Despite my illiteracy in terms of physics I recognised the structure of your dissertation and saw a parallel between our research-processes as discussed in our respective introductions. During the first stages of our research we both were confronted with a fallacy in our basic assumptions, which changed the substances we worked with. If I understand correctly this meant in your case that a quality that you projected onto silver bromide and that was needed for the experiments central to the research method did not exist. In my case it meant that the position of photographs in my study shifted from being a way to get access to aspects of a particular cultural context to being its subject. 
The title of your dissertation mentions what it is about, mine also includes what could be thought of as a discipline and positions it as a method: ‘in and through an artistic practice’. This implies that the how of the research is as much at stake as the what. I take this to be the fundamental difference between our otherwise overlapping interests and ambitions to contribute to the development of knowledge. 
At this point it might be useful to introduce the term affordances. I only came across it when finalising my dissertation and used it casually in the conclusion, but want to explore it further while working with your legacy. Psychologist James Gibson proposed to think of all organisms as beings in an environment that offers affordances, possibilities. These affordances are not fixed but relative to the organism that actives them.
Allow me to illustrate this by constructing a string of affordances, starting from your training as a chemist, which could have led to a career in a university lab. You, however, made it into an affordance that allowed -gave you a reason- to travel. Browsing through your photographs it seems to me that the camera that you brought with you on these journeys afforded you to approach people in different ways than taking their blood samples did. In the former case these people were individuals with an agency that they brought to the encounter to a bigger or smaller extent. In the latter case the individuals formed a line, waiting to be taken blood from. They were turned into a source of data before receiving some salt or tobacco in return. The photographs that resulted from these encounters afforded, for you, communication about your experiences in publications and lectures and for your audiences to imagine ‘Africa’. These same photographs now afford for you to be remembered as a photographer, as your legacy is in the care of the Nederlands Fotomuseum in Rotterdam. They afford for me to bring something when I travel to the same places you once visited. They also afford me to experience the affordances your photographs have for the descendants of the people connected to who and what you once photographed. And they will afford the audiences to the outcome of my artistic practice to engage with all of this from their position. 
British anthropologist Paul Basu currently leads a research project called ‘Museum affordances’, which is “investigating the latent possibilities of museum collections, curatorial interventions and innovative exhibition practices.” To do this the ‘Museum Affordances’ project works with data collected by colonial anthropologist N.W. Thomas: his notes, objects, sound recordings and photographs. The project builds on the premise that there are affordances tacitly present in Thomas’s materials that can only be activated by people who connect to them in other ways than a British team of researchers can do. Materials are brought to where they were once collected and which in turn informs them. In the process the position of N.W. Thomas is made relative to what the material he collected and produced affords while it is kept in British museums. I only got to know about this project recently, but consider it to be related to what I, several years ago, started to do with your legacy. I intend to look beyond the output of the way you were disciplined and see what this affords. Meanwhile I am curious as to whether and how the central position of artistic practice as method may have other affordances than a more conventionally disciplined vantage point.
I will end this letter with an experience that may say something about the affordances of ‘making’ as a tool to investigate your material. This example concerns the photographs and film footage you produced in 1932, while being hosted by Kwei Dokie, chief of the Manoh in Sanniquellie. 
The name Dokie immediately rang a bell when I mentioned it to the man who was driving me upcountry in Liberia in 2013. One of the first victims of the Charles Taylor regime, leading up to the civil war in the country in the 1990s, was Samuel Dokie, member of a prominent family in Sanniquellie. It indeed turned out to be easy to find family members of Samuel Dokie, who all identified as descendants of the chief you photographed. I was first introduced to mr. James Moore, who was burdened with the responsibility of passing on the family history. He knew stories about his ancestor who was an important chief in the early 20th century, but had never seen him. He told me all he knew about Kwei Dokie, and I gave him copies of your photographs.
When I returned to Liberia, a year later, I also had access to digitised versions of the film you made about your journey through Liberia. The titles you added to the footage mention that a party was organised in your honour, and that the chief, who you call a King enjoyed himself at the dance. So did Dokie’s descendants when watching the film. 
After the screening a lady approached me. She introduced herself as someone who married into the family. Her mother, she said, was 106 and lived with her. She would like for her mother to be remember, just like Chief Kwei Dokie. Would it be possible for me to come and film her? 
The next day I paid a visit. Mother was beautifully dressed but did not seem to be aware of her immediate environment. Her daughter switched on a sound system and played music from her mother’s youth. As soon as the eyes of the elderly lady sparked with recognition and life. A gap between her past and our present was bridged by music and documented in film by me as an affordance of film footage produced by you eighty-two years earlier. In addition, the excess of description that is part the photographic capture shows a reality full of care behind a façade that, at least to my western eyes signifies poverty.
Our interest in anthropology and the privileges that allow(ed) us to travel affords so much more than data, doesn’t it? This raises the question what kind of impact the documents we produce could afford, which is what I will be thinking about towards a next letter to you.
With warm regards,
An earlier version of this letter was performed during the so-called ‘Joined Session’ of the doctoral candidates of Doc-Artes and PhDArts, Leiden University, March 2019