KLI Colloquia are invited research talks of about an hour followed by 30 min discussion. The talks are held in English, open to the public, and offered in hybrid format.
Fall-Winter 2025-2026 KLI Colloquium Series
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https://us02web.zoom.us/j/5881861923?omn=85945744831
Meeting ID: 588 186 1923
25 Sept 2025 (Thurs) 3-4:30 PM CET
A Dynamic Canvas Model of Butterfly and Moth Color Patterns
Richard Gawne (Nevada State Museum)
14 Oct 2025 (Tues) 3-4:30 PM CET
Vienna, the Laboratory of Modernity
Richard Cockett (The Economist)
23 Oct 2025 (Thurs) 3-4:30 PM CET
How Darwinian is Darwinian Enough? The Case of Evolution and the Origins of Life
Ludo Schoenmakers (KLI)
6 Nov (Thurs) 3-4:30 PM CET
Common Knowledge Considered as Cause and Effect of Behavioral Modernity
Ronald Planer (University of Wollongong)
20 Nov (Thurs) 3-4:30 PM CET
Rates of Evolution, Time Scaling, and the Decoupling of Micro- and Macroevolution
Thomas Hansen (University of Oslo)
4 Dec (Thurs) 3-4:30 PM CET
Chance, Necessity, and the Evolution of Evolvability
Cristina Villegas (KLI)
8 Jan 2026 (Thurs) 3-4:30 PM CET
Embodied Rationality: Normative and Evolutionary Foundations
Enrico Petracca (KLI)
15 Jan 2026 (Thurs) 3-4:30 PM CET
On Experimental Models of Developmental Plasticity and Evolutionary Novelty
Patricia Beldade (Lisbon University)
29 Jan 2026 (Thurs) 3-4:30 PM CET
Jan Baedke (Ruhr University Bochum)
Event Details

Topic description / abstract:
From the Hippocratic theory of disease as disturbance between the four humors to the bio-statistical theory of disease (and health), philosophers have been trying (unsuccessfully until now) for a long time already to analyze the elusive concept of disease. Giving a correct (and complete) analysis of (the concept of) disease is an urgent and important task.
In the contemporary philosophical literature about disease, we can usefully distinguish between three groups of theories of disease, which may be labeled “axiologism about disease”, “dysfunctionalism about disease” and “hybridism about disease”. These three groups of theories of disease are distinguished with respect to the intuition(s) that we have about what disease is.
Axiologism about disease accounts for the intuition that (i) saying that e.g. one’s lung tissues have cancer is making a specific negative value judgement toward one’s lung tissues, where the value at issue is intuitively a lethal one (like death), by contradistinction with a vital value like health and life.
Dysfunctionalism about disease takes into consideration the intuition that (ii) saying that one’s lung tissues have cancer is saying that one’s lung tissues are biologically dysfunctional.
While many theories of disease have further analyzed either intuition (i) or (ii), it is obvious that a complete theory of disease should coherently analyze both intuitions (i) and (ii). Thence, a third and last group of theories of disease coined “hybridism about disease” has quickly arisen.
In this talk, after presenting (and illustrating) the above three groups of theories of disease, I thoroughly argue for an original hybrid theory of disease called “essentialism about disease”, according to which x is diseased, if and only if x is a healthy processual part of an organism, and x has a specific lethal value i.e. that x hosts properties destroying x’s essence.
Biographical note:
François Pellet is a philosopher of science with a research focus on philosophy of (evolutionary) biology and of medicine. He is currently working as a PhD student at the University of Münster within the Münster Graduate School of Evolution on a DAAD-funded research project, under the supervision of Prof. Dr. Ulrich Krohs, on the nature of disease.
He was awarded his MA degree in philosophy with a specialization in philosophy of science at the University of Geneva in 2015 with a MA dissertation, under the supervision of Prof. Dr. Marcel Weber, entitled “Computer simulations: A definition.”