Humboldt-Universität zu Berlin - Department of Philosophy - Philosophy, Science and the Sciences

Christopher Roser

Christohper RoserMy research concentrates mainly on rationality and reasons, and on several related issues in epistemology, practical philosophy, and history of philosophy. I am particularly interested in justifications of the normativity of rationality, in theory of argumentation, the idea of a rational or philosophical life and the history of rationality. I am working mainly on ancient sophistry and rhetoric (specifically on Gorgias, Antiphon and Isocrates), Plato, and Aristotle.

Thesis: Philosophy and the expertise in logos – On the conceptualization and justification of rationality in Plato and in Ancient Sophistry and Rhetoric.

How can one spell out what is rational and reasonable – before one has a formal logic at hand? And how can one justify that it is important to be rational and reasonable in a non-trivial way? How to solve the deep disagreement between two parties adhering to different standards of rationality? Moreover, the more historical questions: How did ideas about what is rational and reasonable and that it is important to be rational and reasonable appear at the beginning of philosophy in Ancient Greece? These are the leading questions in my study on Plato’s dialogues – specifically Gorgias, Protagoras and Euthydemus – and ancient sophistical and rhetorical texts – specifically in Gorgias, Antiphon, Alcidamas and Isocrates.

Several ancient sophists and rhetoricians agree with Plato’s Socrates on the importance of rationality. They argue for a position one can call rationalism or intellectualism: they argue that one should pursue certain rational or intellectual abilities and states, and that they are of central importance for living well. Specifically, they take the position that it is important to be able to use reasons and arguments rightly and to obtain in this way a good epistemic state. And they justify this position and face the criticism against such a view.

I study how this rationalism is spelled out and justified. I examine how Plato and how these sophists and rhetoricians conceive of reasons and arguments and how they justify that one should follow reasons and arguments in believing, acting and living. One important aspect of the research is this with Plato’s conception of philosophy and with the rhetorical expertise in logos (peri tous logous). I argue that the rhetorical and sophist conceive of this expertise to be an expertise in arguing well.

I am particularly interested in the connection between Plato’ and these sophists’ and rhetoricians’ views on this matter: In how far does Plato overtake or modified certain aspects of the sophists’ and rhetoricians’ conception of arguments and reasons? How does he argue for his conception in opposition to their conception? How is his conception of dialectics and philosophy related to their concept of rhetoric and the expertise in logos?

It is the aim of the thesis to contribute to a better understanding of how one can conceptualize rationality and how one can argue for the normativity of rationality. And it is the aim to contribute to the history of rationality, reason and argumentation. One aspect of this is to study the meaning and history of “logos”.

CV: Christopher studied Philosophy, Logic and Theory of Science at the LMU Munich and the University of Oxford and Classics at the University of Cambridge, since 2013 he does PhD research at the Research Training Group Philosophy, Science and the Sciences with Jonathan Beere as his supervisor.