I am researcher at DebateLab at Karlsruhe Institute of Technology (KIT), trainer at Institute of Argumentation Competence in Berlin and founder of Forum für Streitkultur (with Romy Jaster). I am analyzing and reconstructing populist arguments in current political debates with a particular interest in how the quality of these debates can be improved.

My work is driven by a strong passion for communication and argumentation. I strongly believe that argument is the means to solve disputes and coordinate (doxastic) differences between people. We need constructive conflict

  • in academia to facilitate scientific progress,
  • in politics and society to recognize and respect other people's opinions,
  • in companies to promote innovations, and
  • in private life to get along with and learn from each other.

We (again and again) need to be confronted with different beliefs, perspectives, and ways of life. Only then can we treat each other with tolerance, openness, and respect. This has tragically become evident once again in the recent rise of populism in Europe and the United States. I am convinced that inclusive and interdisciplinary approaches in industry, society, and science are the key to the most pressing problems of our time. No single person, party, or discipline can solve them single-handedly. The (academic) study of philosophy has taught me that the way to truth is constructive conflict.

Romy Jaster / David Lanius__David: Die Wahrheit schafft sich ab - Wie Fake News Politik machen
Romy Jaster's and my book on fake news has been published on 15 February 2019 by Reclam and is available on Amazon.de and Bücher.de (in German).
David Lanius: Strategic Indeterminacy in the Law
My book on strategic indeterminacy in the law has been published on 27 June 2019 by Oxford University Press and is available on Bookdepository.com, Amazon.de, and Bücher.de (in English).

My most recent argumentation analysis has been on the AfD electoral platform and can be found here (in German). At the moment, I am pursuing three related projects at DebateLab:

  • Analyzing the Argumentative Practices of Populism (description)
  • Analyzing and Assessing the Public Debate in Germany (description)
  • Laying the Foundations of a Normative Theory of Public Debate (description)
I have just co-edited (with Ioannis Votsis) a special issue on Towards Foolproof Democracy in the journal Moral Philosophy and Politics (loosely based on a joint conference on "Improving Public Debate and Political Decision-Making: The Last Democracy Conference before Brexit?" organized by the Philosophy Faculty at NCH and the Institute of Philosophy at KIT that took place in London from 28 to 29 March 2019).
Short CV
2017 – today PostDoc at DebateLab at Karlsruhe Institute of Technology (KIT) with Gregor Betz
  Fellow at Weizenbaum Institute in the project "News, Campaigns and the Rationality of Public Discourse" in 2019
2012 – 2017 PhD at Humboldt-Universität zu Berlin with the research project "Dealing Reasonably with Blurred Boundaries" under the supervision of Geert Keil and Ralf Poscher (summa cum laude)
  Dissertation title: "Strategic Indeterminacy in the Law" (published with Oxford University Press)
  Research semester at University of Southern California (USC) in LA with Andrei Marmor in 2014
2010 – 2011 Logic Year at Institute of Logic, Language and Computation (ILLC) in Amsterdam
  Thesis title: "Vagueness and Unforeseeability. A Game Theoretical Approach" (pdf)
2007 – 2010 Magister Philosophiae (MPhil) at Ludwig-Maximilians-Universität (LMU) Munich (with distinction)
  Thesis title: "Warum Vagheit nicht Unwissen ist. Eine kritische Analyse der epistemischen Theorie" ("Why Vagueness is Not Ignorance. A Critical Analysis of the Epistemic Theory") (pdf)
  Research year at Universidad Complutense de Madrid (UCM) from 2008 to 2009
2005 – 2007 Basic studies of M.A. in philosophy and economics at Universität Regensburg
Academic Background

I am working as a PostDoc at DebateLab of Karlsruhe Institut für Technologie (KIT) with Gregor Betz on reconstructing populist arguments in current political debates, defining fake news, and developing a normative theory of public debate (in particular, on how norms or standards of debate can be justified). Also, I am a member of the European Network for Argumentation and Public Policy Analysis (APPLY: Cost Action 17132), trying to improve the way European citizens understand, evaluate and contribute to public debate and political decision-making.

I wrote my dissertation in philosophy under the supervision of Geert Keil at Humboldt-Universität zu Berlin, Ralf Poscher at Albert-Ludwigs-Universität Freiburg and Andrei Marmor at Cornell Law School. It has been published with Oxford University Press and is on vagueness and indeterminacy in the wording of laws, verdicts, and contracts. Legal texts are particularly interesting insofar as they address a widely heterogeneous audience, are applied in a wide variety of circumstances and must, at the same time, lay down clear and unambiguous standards. Sometimes they fail to do so, either by accident or by intention. In my dissertation I try to answer three, related, questions. First, what are the sources of indeterminacy in law? Second, what effects do the different forms of indeterminacy have? Third, how can and should they be intentionally used? The dissertation examines the various forms of indeterminacy as they are actually found in legal texts and scrutinises (i.a. by way of game theoretical models) the conditions under which they can be strategically used in laws, verdicts, and contracts.

My main area of specialisation is philosophy of language, logic, and argumentation theory. I very much appreciate the philosophy of Ludwig Wittgenstein as well as the free will debate. I am particularly enthusiastic about philosophical, psychological, legal, and logical aspects of vagueness, but I am also interested in more general questions of philosophy of law, linguistics as well as decision and game theory.

At the moment I am particularly interested in how (and whether) people change their convictions based on rational argumentation. Are good arguments ultimately convincing also to someone who does not share one's beliefs already? How are we to deal with people who believe in "alternative facts?" Are there specific argumentative practices tied to modern populism, or is it all rhetoric?


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