Synthesized answer
The provided passages do not contain enough information to answer the question about the central thesis of Alexander von Humboldt's "Kosmos: Entwurf einer physischen Weltbeschreibung." The passages only include the title of the work and its author [1]. There is no description of the book's content or its core arguments within the given text.
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
Title: Kosmos, Entwurf einer physischen Weltbeschreibung, von Alexander von Humboldt by Alexander von Humboldt