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Who are we?

Sarah Hijmans

I am a PhD student in history and philosophy of chemistry at the Laboratoire Sphère (Université Paris-Diderot) in Paris, France. My research is mainly focused on the concept of chemical element and its historical development, but I am also interested in chemical classifications and laboratory practice.

The main aim of my PhD is to find out how chemists identified chemical elements during the eighteenth- and nineteenth century. In theory, they agreed that a substance was elementary when it could not be decomposed in the lab - but it was not always possible to apply this criterion in practice. It seems that for a new element to be accepted, its similarities to known elements might have been just as important as its indecomposability.

Vanessa Seifert

I am interested in examining standard issues of the philosophy of science, from the novel and relatively unexplored perspective of chemistry. This includes questions such as: how does chemistry contribute to our understanding of the world around us?; what is the relation between chemistry and other sciences like physics and biology; and, do chemical entities and properties like molecules and chemical bonds, exist?


I am currently a teaching fellow at the University of Athens. Previously, I was a post-doctoral research associate with the ERC project 'Metaphysical Unity of Science' (grant no. 771509) at the University of Bristol. 

My undergraduate studies were in Chemical Engineering from the National Technical University of Athens. I then pursued an MSc in Philosophy of Science from the London School of Economics. I completed my PhD in Philosophy under the supervision of James Ladyman at the University of Bristol. 

For more info on what I do, check out my personal website!


Karoliina Pulkkinen

I'm a philosopher of science with a special interest in how values influence chemistry and climate modeling.

I’m currently working as a postdoctoral researcher in KTH Royal Institute of Technology. Prior to moving to Stockholm, I was a Ph.D. candidate at the Department of History and Philosophy of Science at University of Cambridge. In my doctoral research, I investigated the role of values in developing the periodic systems of chemical elements.

In my PhD monograph, I argued that examining the competing periodic systems with the framework of values gives us an especially insightful explanation of their differences. My thesis demonstrates how three chemists – Mendeleev, Julius Lothar Meyer, and John Newlands – emphasised different values when developing their systems in 1863-1875. While no chemist emphasised just one value, I argue that Newlands elevated simplicity (“simple relation”), Mendeleev completeness (polnost’), and Meyer carefulness when systematising the elements. I also identified a relationship between values guiding the development of the systems and chemists’ subsequent uses of their systems. 

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