 Zachariae's last work of importance was "Vierzig Bücher vom Staate" (1839–1842), to which his admirers point as his enduring monument.It has been compared to Montesquieu's "L'Esprit des lois," "The Spirit of the Laws" and covers no small part of the field of Buckle's first volume of the History of Civilization.But though it contains proof of vast erudition and many original ideas as to the future of the state and of law, it lacks logical sequence, and is, consequently, full of contradictions.