Piotrowski proposes a horizontal art history to escape from hegemonic hierarchies in terms of history (which fall within the notion of vertical art history). A horizontal study of art also involves a transnational perspective allowing to show the pluralism of transregional histories. Piotrowski therefore proposes a pluralistic art historical narrative, including several concepts such as “close other”, questioning the role of the margin and its interaction in the center. (P.B.L.)