The article tries to explain the differences between Zich's and Mukařovský's positions with regard to theory of the dramatic theatre due to their different affinities to the three traditions singled out from ancient Greek metaphysics by Jan Patočka. If Zich follows more the materialistic atomist Democritus, Mukařovský adheres more to Aristotle, whose realism holds the middle between atomism and Plato's idealism. As a result of their different philosophical inclinations, the two Czech structuralists interpret the relation between material and form differently. The article follows Mukařovský's gradual development of views focusing on the central ideas in his three main essays: 'Aesthetic Function, Norm and Value as Social Facts' (1936), 'On Poetic Language' (1940), and 'Intentionality and Unintentionality in Art' (1943). The aim of my article is therefore to draw attention to Mukařovský's study and specifically to his key idea of 'semantic gesture' especially in the dramatic genre in literature as well as in the theatre. In a brief sketch of Euripides' tragedy Medea I try to show how the dramatic dialogue lays bare conflicting ideas about social values in ancient Greek democracy.