Alexander von Humboldt aimed »to grasp the whole world«. He searched the unknown in order to explain that which was close but incomprehensible as a result of being seen in isolation from the network to which it belongs. All natural, cultural and social phenomena are interrelated and should be studied as a whole. Contrary to a hierarchical scientific methodology based on a first principle that supports the whole, Humboldt conceives a complex network in which every individual element is equally important, despite each having its own unique dimensions and logic. Humboldt's natural studies, classifications, and measurements, as well as his social, artistic, cultural, political and economic research, make up a theory of the cosmos that connects all of these different spheres. This book brings together researchers from several fields to reflect on the meaning of »the whole world«, not only in the context of Humboldt's legacy (Part I), but also in line with the thought of other political scientists before and after Humboldt (Part II) and from the perspective of culture and the arts (Part III).