The Epistemic Value of Logos

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.